Extended release microparticles and suspensions thereof for medical therapy

ABSTRACT

An improved microparticle or lyophilized or otherwise reconstitutable microparticle composition thereof for medical therapy, including ocular therapy.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is continuation of U.S. patent application No. claimsthe benefit of U.S. application Ser. No. 16/821,738, filed Mar. 17,2020, which is a continuation of U.S. patent application Ser. No.15/976,847, filed May 10, 2018, which claims the benefit of provisionalU.S. Application Nos. 62/504,366, filed May 10, 2017 and 62/508,355,filed May 18, 2017. The entirety of each of these applications is herebyincorporated by reference for all purposes.

FIELD OF THE INVENTION

This invention is in the area of improved microparticles, lyophilized orotherwise solidified microparticles, or microparticle suspensions, andprocesses thereof, which can, optimally, be loaded with an active drugor a prodrug of an active drug, for use in medical drug delivery,including for ocular drug delivery.

BACKGROUND

The structure of the eye can be divided into two segments referred to asthe anterior and posterior. The anterior segment comprises the frontthird of the eye and includes the structures in front of the vitreoushumor: the cornea, iris, ciliary body, and lens. The posterior segmentincludes the back two-thirds of the eye and includes the sclera,choroid, retinal pigment epithelium, neural retina, optic nerve, andvitreous humor.

Important diseases affecting the anterior segment of the eye includeglaucoma, allergic conjunctivitis, anterior uveitis, and cataracts.Diseases affecting the posterior segment of the eye include dry and wetage-related macular degeneration (AMD), cytomegalovirus (CMV) infection,diabetic retinopathy, choroidal neovascularization, acute macularneuroretinopathy, macular edema (such as cystoid macular edema anddiabetic macular edema), Behcet's disease, retinal disorders, diabeticretinopathy (including proliferative diabetic retinopathy), retinalarterial occlusive disease, central retinal vein occlusion, uveitisretinal disease, retinal detachment, ocular trauma, damage caused byocular laser treatment or photodynamic therapy, photocoagulation,radiation retinopathy, epiretinal membrane disorders, branch retinalvein occlusion, anterior ischemic optic neuropathy, non-retinopathydiabetic retinal dysfunction and retinitis pigmentosa. Glaucoma issometimes also considered a posterior ocular condition because atherapeutic goal of glaucoma treatment is to prevent or reduce the lossof vision due to damage or loss of retinal cells or optic nerve cells.

Typical routes of drug administration to the eye include topical,systemic, intravitreal, intraocular, intracameral, subconjunctival,sub-tenon, retrobulbar, and posterior juxtascleral. (Gaudana, R., etal., “Ocular Drug Delivery”, The American Association of PharmaceuticalScientist Journal, 12(3)348-360, 2010).

A number of types of delivery systems have been developed to delivertherapeutic agents to the eye. Such delivery systems includeconventional (solution, suspension, emulsion, ointment, inserts, andgels), vesicular (liposomes, niosomes, discomes, and pharmacosomes),advanced materials (scleral plugs, gene delivery, siRNA, and stemcells), and controlled-release systems (implants, hydrogels, dendrimers,iontophoresis, collagen shields, polymeric solutions, therapeuticcontact lenses, cyclodextrin carriers, microneedles, microemulsions, andparticulates (microparticles and nanoparticles)).

Treatment of posterior segment diseases remains a daunting challenge forformulation scientists. Drug delivery to the posterior segment of theeye is typically achieved via an intravitreal injection, the periocularroute, implant, or by systemic administration. Drug delivery to theposterior segment by way of the periocular route can involve theapplication of a drug solution to the close proximity of the sclera,resulting in high retinal and vitreal concentrations.

Intravitreal injection is often carried out with a 30 gauge or lessneedle. While intravitreal injections offer high concentrations of drugto the vitreous chamber and retina, they can be associated with variousshort-term complications such as retinal detachment, endophthalmitis,and intravitreal hemorrhages. Experience shows that injection of smallparticles can lead to the rapid dispersal of the particles that canobstruct vision (experienced by the patient as “floaties” or “floaters”)and the rapid removal of the particles from the injection site (whichcan occur via the lymphatic drainage system or by phagocytosis). Inaddition, immunogenicity can occur upon recognition of the microspheresby macrophages and other cells and mediators of the immune system.

Complications in periocular injections include increased intraocularpressure, cataract, lur, strabismus, and corneal decompensation.Transscleral delivery with periocular administration is seen as analternative to intravitreal injections. However, ocular barriers such asthe sclera, choroid, retinal pigment epithelium, lymphatic flow, andgeneral blood flow can compromise efficacy. Systemic administration,which is not advantageous given the ratio of the volume of the eye tothe entire body, can lead to potential systemic toxicity.

A number of companies have developed microparticles for treatment of eyedisorders. For example, Allergan has disclosed a biodegradablemicrosphere to deliver a therapeutic agent that is formulated in a highviscosity carrier suitable for intraocular injection or to treat anon-ocular disorder (U.S. publication 2010/0074957 and U.S. publication2015/0147406 claiming priority to a series of applications back to Dec.16, 2003). In one embodiment, the '957 application describes abiocompatible, intraocular drug delivery system that includes aplurality of biodegradable microspheres, a therapeutic agent, and aviscous carrier, wherein the carrier has a viscosity of at least about10 cps at a shear rate of 0.1/second at 25° C.

Allergan has also disclosed a composite drug delivery material that canbe injected into the eye of a patient that includes a plurality ofmicroparticles dispersed in a media, wherein the microparticles containa drug and a biodegradable or bioerodible coating and the media includesthe drug dispersed in a depot-forming material, wherein the mediacomposition may gel or solidify on injection into the eye (WO2013/112434 A1, claiming priority to Jan. 23, 2012). Allergan statesthat this invention can be used to provide a depot means to implant asolid sustained drug delivery system into the eye without an incision.In general, the depot on injection transforms to a material that has aviscosity that may be difficult or impossible to administer byinjection.

In addition, Allergan has disclosed biodegradable microspheres between40 and 200 μm in diameter, with a mean diameter between 60 and 150 μmthat are effectively retained in the anterior chamber of the eye withoutproducing hyperemia (US 2014/0294986). The microspheres contain a drugeffective for an ocular condition with greater than seven-day releasefollowing administration to the anterior chamber of the eye. Theadministration of these large particles is intended to overcome thedisadvantages of injecting 1-30 μm particles which are generally poorlytolerated.

Regentec Limited has filed a series of patent applications on thepreparation of porous particles that can be used as tissue scaffolding(WO 2004/084968 and U.S. publication 2006/0263335 (filed Mar. 27, 2003)and U.S. publication 2008/0241248 (filed Sep. 20, 2005) and WO2008/041001 (filed Oct. 7, 2006)). The porosity of the particles must besufficient to receive cells to be held in the particle. The cells can beadded to the matrix at, or prior to, implantation of the matrix orafterward in the case of recruitment from endogenous cells in situ.Regentec also published an article on tissue scaffolding with porousparticles (Qutachi et al. “Injectable and porous PLGA microspheres thatform highly porous scaffolds at body temperature”, Acta Biomaterialia,10, 5080-5098, (2014)).

In addition, Regentec Limited also filed patent applications on thepreparation of large porous particles that can be used in drug delivery(WO 2010/100506 and U.S. publication 2012/0063997 (filed Mar. 5, 2009)).The porosity of the particles allows for quick delivery of thetherapeutic agent. The particles are intended to form a scaffold thatfills the space in which they are injected by a trigger such as a changein temperature.

Additional references pertaining to highly porous microparticles includepublications by Rahman and Kim. Rahman et al. “PLGA/PEG-hydrogelcomposite scaffolds with controllable mechanical properties” J. ofBiomedical Materials Research, 101, 648-655, (2013) describes hydrogelsof approximately 50 percent porosity and their corresponding mechanicalproperties. Kim et al. “Biodegradable polymeric microspheres with“open/closed” pores for sustained release of human growth hormone” J. ofControlled Release, 112, 167-174, (2006) describes PLGA polymers withpores for the delivery of human growth hormone.

EP 2125048 filed by Locate Therapeutics Limited (filed Feb. 1, 2007) aswell as WO 2008/093094, U.S. publication 2010/0063175 (filed Feb. 1,2007), and WO 2008/093095 (filed Feb. 1, 2007) filed by Regentec Limiteddisclose the preparation of particles that are not necessarily porousbut that when exposed to a trigger (such as temperature) form a tissuescaffold useful in the repair of damaged or missing tissue in a host.

U.S. Pat. No. 9,161,903 issued on Oct. 20, 2015 to Warsaw Orthopedic andU.S. publication 2016/0038407 filed by Warsaw Orthopedic Inc. disclose aflowable composition for injection at a target tissue site beneath theskin that includes a flowable composition that hardens at or near thetarget tissue site.

Bible et al. “Attachment of stem cells to scaffold particles forintra-cerebral transplantation”, Nat. Protoc., 10, 1440-1453, (2009)describes a detailed process to make microparticles of PLGA that do notclump or aggregate.

U.S. Patent Application Publication 2011/0123446 filed by LiquidiaTechnologies titled “Degradable compounds and methods of use thereof,particularly with particle replication in non-wetting templates”describes degradable polymers that utilize a silyl core and can formrapidly degrading matrixes.

Additional references pertaining to particles for ocular deliveryinclude the following. Ayalasomayajula, S. P. and Kompella, U. B. havedisclosed the subconjunctival administration of celecoxib-poly(lactideco-glycolide) (PLGA) microparticles in rats (Ayalasomayajula, S. P. andKompella, U. B., “Subconjunctivally administered celecoxib-PLGAmicroparticles sustain retinal drug levels and alleviatediabetes-induced oxidative stress in a rat model”, Eur. J. Pharm., 511,191-198 (2005)). Danbiosyst UK Ltd., has disclosed a microparticlecomprising a mixture of a biodegradable polymer, a water soluble polymerof 8,000 Daltons or higher and an active agent (U.S. Pat. No.5,869,103). Poly-Med, Inc. has disclosed compositions comprising ahydrogel mass and a carrier having a biological active agent depositedon the carrier (U.S. Pat. No. 6,413,539). MacroMed Inc. has disclosedthe use of an agent delivery system comprising a microparticle and abiodegradable gel (U.S. Pat. Nos. 6,287,588 and 6,589,549). Novartis hasdisclosed ophthalmic depot formulations for periocular orsubconjunctival administration where the pharmacologically acceptablepolymer is a polylactide-co-glycolide ester of a polyol (U.S.publication 2004/0234611, U.S. publication 2008/0305172, U.S.publication 2012/0269894, and U.S. publication 2013/0122064). TheUniversidad De Navarra has disclosed oral pegylated nanoparticles forcarrying biologically active molecules comprising a pegylatedbiodegradable polymer (U.S. Pat. No. 8,628,801). Surmodics, Inc. hasdisclosed microparticles containing matrices for drug delivery (U.S.Pat. No. 8,663,674). Minu, L.L.C., has disclosed the use of an agent inmicroparticle of nanoparticle form to facilitate transmembranetransport. Emory University and Georgia Tech Research Corporation havedisclosed particles dispersed in a non-Newtonian fluid that facilitatesthe migration of the therapeutic particles from the insertion site inthe suprachoroidal space to the treatment site (U.S. 2016/0310417).Pfizer has disclosed nanoparticles as injectable depot formulations(U.S. publication 2008/0166411). Abbott has disclosed a pharmaceuticaldosage form that comprises a pharmaceutically acceptable polymer for thedelivery of a tyrosine kinase inhibitor (U.S. publication 2009/0203709).The Brigham and Woman's Hospital, Inc. has disclosed modifiedpoly(lactic-co-glycolic) polymers having therapeutic agents covalentlybound to the polymer (U.S. 2012/0052041). BIND Therapeutics, Inc. hasdisclosed therapeutic nanoparticles comprising about 50 to 99.75 weightpercent of a diblock poly (lactic) acid-poly(ethylene)glycol copolymeror a diblock poly (lactic acid-co-glycolic acid)-poly(ethylene)glycolcopolymer wherein the therapeutic nanoparticle comprises 10 to about 30weight percent poly(ethylene)glycol (U.S. publication 2014/0178475).Additional publications assigned to BIND Therapeutics, Inc. include U.S.publication 2014/0248358 and U.S. publication 2014/0249158. Allergan hasdisclosed the use of biodegradable microspheres containing a drug totreat an ocular condition (U.S. publication 2010/0074957, U.S.publication 2014/0294986, U.S. publication 2015/0147406, EP 1742610, andWO 2013/112434). Allergan has also disclosed a biocompatible implantcontaining a prostamide component, which can exist in particle form, anda biodegradable polymer that allows for slow release of the drug overthe course of 1 week to 6 months for the treatment of an ocularcondition, such as glaucoma (U.S. application 2015/0157562 and U.S.application 2015/0099805). Jade Therapeutics has disclosed formulationscontaining an active agent and a polymer matrix that can be delivereddirectly to the target tissue or placed in a suitable delivery device(U.S. publication 2014/0107025). Bayer Healthcare has disclosed atopical ophthalmological pharmaceutical composition comprising sunitiniband at least one pharmaceutically acceptable vehicle (WO 2013/188283).pSivida Us, Inc. has disclosed biodegradable drug eluting particlescomprising a microporous or mesoporous silicon body for intraocular use(U.S. Pat. No. 9,023,896). Additional patents assigned to pSivida Us,Inc. include: U.S. Pat. Nos. 8,871,241; 8,815,284; 8,574,659; 8,574,613;8,252,307; 8,192,408 and 7,998,108. ForSight Vision4, Inc. has disclosedtherapeutic devices for implantation in the eye (U.S. Pat. No.8,808,727). Additional patents assigned to ForSight Vision4, Inc.include: U.S. Pat. Nos. 9,125,735; 9,107,748; 9,066,779; 9,050,765;9,033,911; 8,939,948; 9,905,963; 8,795,712; 8,715,346; 8,623,395;8,414,646; 8,399,006; 8,298,578; 8,277,830; 8,167,941; 7,883,520;7,828,844 and 7,585,075. The Nagoya Industrial Science ResearchInstitute has recently disclosed the use to liposomes to deliver a drugto the posterior segment of the eye (U.S. Pat. No. 9,114,070).

Johns Hopkins University has filed a number of patents claimingformulations for ocular injections including WO2013/138343 titled“Controlled Release Formulations for the Delivery of HIF-1 Inhibitors”,WO2013/138346 titled “Non-linear Multiblock Copolymer-drug Conjugatesfor the Delivery of Active Agents”, WO2011/106702 titled “SustainedDelivery of Therapeutic Agents to an Eye Compartment”, WO2016/025215titled “Glucorticoid-loaded Nanoparticles for Prevention of CornealAllograft Rejection and Neovascularization”, WO2016/100392 titled“Sunitinib Formulations and Methods for Use Thereof in Treatment ofOcular Disorders”, WO2016/100380 titled “Sunitinib Formulation andMethods for Use Thereof in Treatment of Glaucoma”, WO2016/118506 titled“Compositions for the Sustained Release of Anti-Glaucoma Agents toControl Intraocular Pressure”, WO2013/166385 titled “Nanocrystals,Compositions, and Methods that Aid Particle Transport in Mucus”,WO2005/072710 titled “Drug and Gene Carrier Particles that Rapidly moveThrough Mucus Barriers,” WO2008/030557 titled “Compositions and Methodsfor Enhancing Transport through Mucus”, WO2012/061703 titled“Compositions and Methods Relating to Reduced Mucoadhesion,”WO2012/039979 titled “Large Nanoparticles that Penetrate Tissue,”WO2012/109363 titled “Mucus Penetrating Gene Carriers”, WO2013/090804titled “Biodegradable Stealth Nanoparticles Prepared by a NovelSelf-Assembly Emulsification Method,” WO2013/110028 titled“Nanoparticles Formulations with Enhanced Mucosal Penetration”, andWO2013/166498 titled “Lipid-based Drug Carriers for Rapid Penetrationthrough Mucus Linings”.

GrayBug Vision, Inc. discloses prodrugs for the treatment of oculartherapy in US 2018-0036416, US 2018-0064823, US 2018-0110865, US2018-0104350, granted U.S. Pat. Nos. 9,808,531 and 9,956,302 and PCTapplication WO2017/053638. Aggregating microparticles for ocular therapyare described in US 2017-0135960 and WO2017/083779.

In order to treat ocular diseases, and in particular diseases of theposterior segment, the drug must be delivered in therapeutic levels andfor a sufficient duration to achieve efficacy. This seeminglystraightforward goal is difficult to achieve in practice.

The object of this invention is to provide compositions and methods totreat ocular disorders.

SUMMARY

The present invention has at least the following aspects:

-   -   (i) A lyophilized microparticle solid material that has less        propensity to result in floating microparticles than the same        microparticle solid material that has not been processed as        described herein, when resuspended in fluid for example buffered        aqueous solution or aqueous hyaluronic acid, for in vivo        delivery. The process as described herein is based on the        discovery that very small air bubbles or gas or a thin layer of        air adhered to microparticles can adversely affect the quality        of the resuspended microparticle of the present invention, and        that improved microparticles for lyophilization can be provided        by removing adhered air or gas by treating the microparticles        with a vacuum, sonication, or excipient addition or other method        that removes or decreases the adhered air or gas prior to        lyophilization, or by doing so after resuspending the        lyophilized microparticle material. It has been discovered that        the issue of air adhered to the microparticle can be more        pronounced if the microparticle has been surface treated even        under mild conditions to remove or decrease surface surfactant,        such as those described in U.S. Ser. No. 15/349,985 and        PCT/US16/61706 (see nonlimiting Example 2 below).    -   (ii) An improved lyophilized microparticle, microparticle        suspension, and method for manufacture thereof, processed as        described in (i) that is loaded with a pharmaceutically active        agent, including those listed below, which can be active in the        form delivered or is a prodrug, with non-limiting examples        provided herein, for in vivo treatment of a patient in need        thereof.    -   (iii) Microparticles as described herein, and lyophilized or        suspended materials thereof, whether treated to remove adhered        air or gas, and which include any of the active drugs, including        prodrugs, described herein.

For example, it has been identified that for certain applications, theprocesses and materials in U.S. Ser. No. 15/349,985 and PCT/US16/61706provide acceptable aggregating microparticles in vivo, however, thereare occasions when if surface-treated microparticles are overtreated(e.g., treated under strong chemical conditions or for an extendedperiod of time), they may have a tendency to float upon injection intoan aqueous solution with low viscosity (e.g., PBS buffer solution orsometimes vitreal fluid, wherein the viscosity may decrease with age ofthe patient), which is disadvantageous for forming a pellet that remainsout of the visual axis. Since ocular disorders increase with age, it isimportant to provide a particle suspension that still aggregates to apellet in lower viscosity vitreous fluid. Certain aspects of thisinvention address those certain situations, where a thin layer of air,air bubbles or gas generally can adhere to the surface of somemicroparticles and prevent the particles from being completely wetted.If this tiny layer of air or bubbles is high enough to create buoyancy,the microparticles will be less likely to aggregate to the desiredpellet.

Thus, according to the present invention, microparticles andmicroparticle suspensions are provided that have improved aggregation toa pellet for medical therapy due to enhanced wettability in vivo.Examples of processes that provide improved aggregation of particles tothe desired ocular pellet include, but are not limited to, one or acombination of 1) applying a vacuum to the particle suspension tofacilitate the disassociation of air from particles; 2) adding one ormore excipients to reduce surface hydrophobicity of particles and thusreduce the amount of air adhering to the particles; and, 3) sonicationto facilitate the disassociation of air from the particles, either priorto lyophilization or other drying means to make a solid reconstitutablemicroparticle material, or by carrying out one or more of theseprocesses after reconstitution. These processes are described in moredetail below.

In the third independent aspect of the invention, solid microparticlesthat aggregate in vivo to a pellet and provide release of a therapeuticagent in vivo are provided. In certain embodiments, the therapeuticagent is a lipophilic prodrug as described herein. In certainembodiments, the lipophilic prodrug releases a prostaglandin, carbonicanhydrase inhibitor, receptor tyrosine kinase inhibitor (RTKIs), Rhokinase (ROCK) inhibitor, beta-blocker, alpha-adrenergic agonist, or loopdiuretic. In certain embodiments, the therapeutic agent is the activeagent itself not in prodrug form, such as a prostaglandin, a carbonicanhydrase inhibitor, a receptor tyrosine kinase inhibitor (RTKIs), a Rhokinase (ROCK) inhibitor, a beta-blocker, an alpha-adrenergic agonists,or a loop diuretic. Nonlimiting examples of prodrugs and active agentsthat can be used in the present invention are provided herein. Forexample, one or more of the processes can be used at the time theparticles are being prepared to produce the powder or material that isstored and then later resuspended (for example, prior to lyophilization)for injection. In one example, the vessel with the dried microparticlescan be placed under pressure for storage before use. In anothernon-limiting example, the container storing the surface-treatedmicroparticles can be placed under vacuum directly beforeadministration. In other embodiments, it is not necessary to remove airor gas from the active-loaded microparticle at any stage of manufactureto achieve a suitable therapeutic effect.

In typical embodiments of invention (i) above, the process to preparethe improved suspension for medical use, including for administrationinto low viscosity fluids, is conducted following mild surfacetreatment, isolation, and reconstitution in an appropriate diluent.Non-limiting illustrations in Examples 32-37 establish that treatmentsto provide an improved suspension of microparticles upon injection in anaqueous solution result in less floatation and better aggregationcompared to microparticles that have not been treated for enhancedwettability. FIGS. 22A-22C and 23A-23L illustrate the effect of vacuumstrength on particle floatation and aggregation, and FIGS. 27A-27Lillustrate the effect of excipient addition on particle floatation andaggregation. FIGS. 29A, 29B and 30 depict the effect of sonication onparticle floatation and aggregation.

In one embodiment of a selected aspect of the invention, themicroparticles are mildly surface treated prior to treatments forenhanced wettability. In one embodiment, the solid biodegradablemicroparticles are suitable for ocular injection, at which point theparticles aggregate to form a pellet that remains outside the visualaxis so as not to significantly impair vision. The particles canaggregate into one or several pellets. The size of the aggregate dependson the concentration and volume of the microparticle suspensionsinjected and the diluent in which the microparticles are suspended.

In one aspect of the invention, the improved process of (i) forpreparing a microparticle or lyophilized or otherwise solidifiedmaterial thereof or a suspension thereof, leading to an aggregatedpellet in vivo, can be used in combination with a selected method andfor forming aggregating microparticles described in U.S. Ser. No.15/349,985 and PCT/US16/61706 (and the resulting materials thereof). Forexample, methods include providing solid aggregating microparticles thatinclude at least one biodegradable polymer, wherein the solidaggregating microparticles have a solid core, include a therapeuticagent, have a modified surface which has been treated under mildconditions at a temperature, that may optionally be at or less thanabout 18° C., to remove surface surfactant, are sufficiently small to beinjected in vivo, and are capable of aggregating in vivo to form atleast one pellet of at least 500 μm in vivo to provide sustained drugdelivery in vivo for at least three months, four months, five months,six months seven months, eight months, nine months or more. In certainembodiments, sustained drug deliver in vivo is provided for up to oneyear. The solid aggregating microparticles are suitable, for example,for an intravitreal injection, implant, including an ocular implant,periocular delivery, or delivery in vivo outside of the eye. In certainembodiments, the therapeutic agent is a prodrug as described herein.

As an illustration, the present invention includes a process for thepreparation of surface-modified solid aggregating microparticles thatare advantageous for pellet formation in vivo, and microparticlematerials made thereby, that includes:

-   -   A. a first step of preparing microparticles comprising one or        more biodegradable polymers by dissolving or dispersing the        polymer(s) and a therapeutic agent in one or more solvents to        form a polymer and therapeutic agent solution or dispersion,        mixing the polymer and the therapeutic agent solution or        dispersion with an aqueous phase containing a surfactant to        produce solvent-laden microparticles and then removing the        solvent(s) to produce polymer microparticles that contain the        therapeutic agent, polymer and surfactant; and    -   B. a second step of mildly treating the surface of        microparticles of step (i) at a temperature at or below about        18, 15, 10, 8 or 5° C. optionally up to about 1, 2, 3, 4, 5, 10,        30, 40, 50, 60, 70, 80, 90 100, 11, 120 or 140 minutes with an        agent that removes surface surfactant, surface polymer, or        surface oligomer in a manner that does not significantly produce        internal pores; and    -   C. isolating the surface treated microparticles; and    -   D. subjecting the microparticles to at least one process        selected from 1) vacuum treatment prior to lyophilization or        other form of reconstitutable solidification, or after the step        of reconstitution wherein the microparticles are suspended in a        diluent and the suspension is placed under vacuum prior to        use; 2) excipient addition, wherein an excipient is added prior        to lyophilization; and 3) sonication, prior to lyophilization or        other form of reconstitutable solidification, or after the step        of reconstitution; 4) sealing the vial containing the dry powder        of particles under vacuum, including but not limited to high        vacuum; or 5) pre-wetting (i.e., resuspending) the        surface-treated microparticles in a diluent for 2-24 hours        before injecting into the eye, for example in a hyaluronic acid        solution or other sterile solution suitable for ocular        injection.

The process of these steps can be achieved in a continuous manufacturingline or via one step or in step-wise fashion as appropriate. The processof step D. above can be carried out following isolation of themicroparticles and/or upon reconstitution prior to injection. In oneembodiment, the surface treated solid biodegradable microparticles donot significantly aggregate during the manufacturing process. In anotherembodiment, the surface treated solid biodegradable microparticles donot significantly aggregate when resuspended and loaded into a syringe.In some embodiments, the syringe is approximately 30, 29, 28, 27, 26 or25 gauge, with either normal or thin wall.

In another nonlimiting embodiment, a process for preparing a suspensioncomprising a microparticle and a pharmaceutically active compoundencapsulated in the microparticle and the resulting materials thereof;which process comprises:

-   -   (a) preparing a solution or suspension (organic phase)        comprising: (i) PLGA or PLA or PLA and PLGA, (ii) PLGA-PEG or        PLA-PEG (iii) a pharmaceutically active compound, for example,        as described herein and (iv) one or more organic solvents;    -   (b) preparing an emulsion in an aqueous polyvinyl alcohol (PVA)        solution (aqueous phase) by adding the organic phase into the        aqueous phase and mixing them until particle formation (for        example at about 3,000 to about 10,000 rpm for about 1 to about        30 minutes);    -   (c) removing additional solvent as necessary using known        techniques;    -   (d) centrifuging or causing the sedimentation of the        microparticle that is loaded with a pharmaceutically active        compound or prodrug thereof;    -   (e) optionally removing additional solvent and/or washing the        microparticle loaded with the pharmaceutically active compound        or prodrug thereof with water;    -   (f) filtering the microparticle loaded with pharmaceutically        active compound or prodrug thereof to remove aggregates or        particles larger than the desired size;    -   (g) optionally lyophilizing the microparticle comprising the        pharmaceutically active compound and storing the microparticle        as a dry powder in a manner that maintains stability for up to        about 6, 8, 10, 12, 20, 22, or 24 months or more; and    -   (h) optionally improving the aggregation potential of the        particles by subjecting the particles to at least one process        selected from 1) vacuum treatment prior to step (g), or after        reconstitution wherein the microparticles are suspended in a        diluent and the suspension is placed under vacuum; 2) excipient        addition, wherein an excipient is added prior to lyophilization;        and 3) sonication prior to step (g), or during reconstitution        wherein the microparticles are suspended in a diluent and        sonicated; 4) sealing the vial containing the dry powder of        particles under vacuum, including but not limited to high        vacuum; or 5) pre-wetting (i.e., resuspending) the        surface-treated microparticles in a diluent for 2-24 hours        before injecting into the eye, for example in a hyaluronic acid        solution or other sterile solution suitable for ocular        injection.

In one embodiment, a process for preparing an improved lyophilizedmaterial or a suspension of microparticles following reconstitutionincludes suspending the particles in a diluent and subjecting theparticles to vacuum treatment at a pressure of about less than about500, 400, 300, 200, 150, 100, 75, 50, 40, 35, 34, 33, 32, 31, 30, 29, 28or 25 Torr for a suitable amount of time to substantially remove airattached to the particles, which in some embodiments can be up to 3, 5,8, 10, 20, 30, 40, 50, 60, 70, 80, or 90 minutes or up to 2, 3, 4, 5, or6, 10, 15 or 24 or more hours. In one embodiment, the vacuum treatmentis conducted with a VacLock syringe in a size of up to at least 10, 20,30, or 60 mL.

In certain non-limiting embodiments, the microparticles are vacuumed ata strength of less than 40 Torr for about 3, 5, 8, 10, 20, 30, 45, 60,75, or 90 minutes. In certain non-limiting embodiments, themicroparticles are vacuumed at a strength less than 40 Torr from about 1to 90 minutes, from about 1 to 60 minutes, from about 1 to 45 minutes,from about 1 to 30 minutes, from about 1 to 15 minutes, or from about 1to 5 minutes.

In certain embodiments, the diluent for suspending particles is ProVisc.In some embodiments, the microparticles are diluted from about 10-foldto about 40-fold, from about 15-fold to about 35-fold, or from about20-fold to about 25-fold. In some embodiments, the diluent forsuspending particles is a 10×-diluted ProVisc (0.1% HA in PBS) solution,a 20×-diluted ProVisc (0.05% HA in PBS) solution, or a 40×-dilutedProVisc (0.025% HA in PBS) solution. In some embodiment, the particlesare suspended in the diluent at a concentration of at least about 100mg/mL, 200 mg/mL, 300 mg/mL, 400 mg/mL, or 500 mg/mL.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates the aggregation of non-surface treated microparticles(NSTMP) (S-1 and S-5) and surface treated microparticles (STMP) (S-3 andS-8) after injection into PBS and incubation at 37° C. for 2 hours. TheNSTMP, S-1 and S-5, started to disperse immediately when the tubes wereinverted after the 2 hour-incubation, while the STMP, S-3 and S-8,remained aggregated at the bottom of the tubes without dispersionthroughout the entire period of observation (about 10 minutes). Samplesfrom left to right are S-1, S-3, S-5 and S-8 (Example 5).

FIG. 2 illustrates the aggregation of surface treated microparticles(STMP) (S-3 and S-8) after injection into HA and incubation at 37° C.for 2 hours. Samples left to right are S-1, S-3, S-5 and S-8 (Example5).

FIG. 3 illustrates the result of in vitro aggregation and dispersion ofparticles after a 2-hour incubation in PBS at 37° C. followed byagitation to detach the aggregates from the bottom of the tubes. Top rowfrom left to right samples: S-1, S-2, S-3, S-4; Bottom row from left toright samples: S-5, S-6, S-7 and S-8 (Example 5).

FIG. 4 illustrates in vitro aggregation of representative surfacetreated microparticles (STMP) treated with PBS/EtOH (sample S-21) aftera 2-hour incubation in PBS at 37° C. followed by agitation by tappingand flicking the tube (Example 6).

FIG. 5 illustrates the in vitro accelerated drug release profile of arepresentative batch of surface treated microparticles (STMP) (S-12)(Example 12). The x-axis is time measured in days and the y-axis iscumulative release percent.

FIG. 6 illustrates the in vitro drug release profiles for samples S-1,S-2, and S-3 in PBS with 1% Tween 20 at 37° C. (Example 13). The x-axisis time measured in days and the y-axis is cumulative release percent.

FIG. 7 illustrates the in vitro drug release profile of S-13, S-14, 5-15and S-16 in PBS with 1% Tween 20 at 37° C. (Example 15). The x-axis istime measured in days and the y-axis is cumulative release percent.

FIG. 8A illustrates the in vitro aggregation of surface treatedmicroparticles (STMP) in 5-fold diluted ProVisc at a concentration of100 mg/mL into 4 mL of PBS after incubation at 37° C. for 2 hours (top)and after incubation at 37° C. for 2 hours followed by shaking at 250rpm for 2 minutes on an orbital shaker (bottom) (Example 17).

FIG. 8B illustrates the in vitro aggregation of surface treatedmicroparticles (STMP) in 5-fold diluted ProVisc at a concentration of100 mg/mL into 4 mL of HA (5 mg/mL solution) after incubation at 37° C.for 2 hours (top) and after incubation at 37° C. for 2 hours followed byshaking at 250 rpm for 2 minutes on an orbital shaker (bottom) (Example17).

FIG. 8C illustrates the in vitro aggregation of surface treatedmicroparticles (STMP) in 5-fold diluted ProVisc at a concentration of200 mg/mL into 4 mL of PBS after incubation at 37° C. for 2 hoursfollowed by shaking at 250 rpm for 2 minutes on an orbital shaker(bottom) (Example 17).

FIG. 8D illustrates the in vitro aggregation of surface treatedmicroparticles (STMP) in 5-fold diluted ProVisc at a concentration of200 mg/mL into 4 mL of HA (5 mg/mL solution) after incubation at 37° C.for 2 hours followed by shaking at 250 rpm for 2 minutes on an orbitalshaker (bottom) (Example 17).

FIG. 9 illustrates photos of aggregates of particles in an ex vivo coweye 2 hours after injection (Example 18).

FIG. 10A are photos of particle aggregates in the vitreous (left) andout of the vitreous (right) following injection of STMP, S-10, suspendedin PBS into the central vitreous of rabbit eyes (Example 19).

FIG. 10B are photos of particle aggregates in the vitreous (left) andout of the vitreous (right) following injection of STMP, S-10, suspendedin 5-fold diluted ProVisc into the central vitreous of rabbit eyes(Example 19).

FIG. 11A illustrates representative 1-month histology images of rabbiteyes injected with surface treated microparticles (STMP) (Example 20).

FIG. 11B illustrates representative 1-month histology images of rabbiteyes injected with non-surface treated microparticles (NSTMP) (Example20).

FIG. 12 illustrates the size distribution of a representative batch ofsurface treated microparticles (STMP) (S-12) (Example 22). The x-axisrepresents particle diameter measured in micrometers and the y-axisrepresents volume percent.

FIG. 13A illustrates select PK profiles for sunitinib in the retinafollowing a bilateral injection of sunitinib malate (free drug) at adose of 0.0125 mg/eye or 0.00125 mg/eye in pigmented rabbits (Example24). The x-axis is time measured in hours and the y-axis is theconcentration of sunitinib in ng/g.

FIG. 13B illustrates select PK profiles for sunitinib in the vitreousfollowing a bilateral injection of sunitinib malate (free drug) at adose of 0.0125 mg/eye or 0.00125 mg/eye in pigmented rabbits (Example24). The x-axis is time measured in hours and the y-axis is theconcentration of sunitinib in ng/g.

FIG. 13C illustrates select PK profiles for sunitinib in the plasmafollowing a bilateral injection of sunitinib malate (free drug) at adose of 2.5 mg/eye, 0.25 mg/eye, or 0.025 mg/eye in pigmented rabbits(Example 24). The x-axis is time measured in hours and the y-axis is theconcentration of sunitinib in ng/g.

FIG. 14 illustrates sunitinib levels (ng/g) in rabbits injected with 10mg of STMP containing 1 mg sunitinib for 7-months post-dose. The rabbitswere sacrificed at 7 months and sunitinib levels (ng/g) were determinedin the vitreous, retina, plasma, and RPE-Choroid. Sunitinib levels wereabove the K_(i) for sunitinib against VEGFR and PDGFR (Example 20). Thex-axis represents time post-dose in month and the y-axis represents theconcentration of sunitinib measured in ng/g.

FIG. 15 illustrates sunitinib levels (ng/g) in rabbits injected with 2mg of STMP containing 0.2 mg sunitinib (10% w/w STMP) for 4-monthspost-dose. The rabbits were sacrificed at 4 months and sunitinib levels(ng/g) were determined in the vitreous, retina, plasma, and RPE-Choroid.Sunitinib levels were above the K_(i) for sunitinib against VEGFR andPDGFR in the RPE-Choroid and retina (Example 20). The x-axis representstime post-dose in months and the y-axis represents the concentration ofsunitinib measured in ng/g.

FIG. 16 illustrates sunitinib levels (ng/g) in rabbits injected with 10mg of STMP containing 0.2 mg sunitinib (2% w/w STMP). The rabbits weresacrificed at 4 months and sunitinib levels (ng/g) were determined inthe vitreous, retina, plasma, and RPE-Choroid. Sunitinib levels wereabove the K_(i) for sunitinib against VEGFR and PDGFR in the RPE-Choroidand retina (Example 20). The x-axis represents time post-dose in monthand the y-axis represents the concentration of sunitinib measured inng/g.

FIG. 17 illustrates the aggregation of surface treated microparticles(STMP) (S-28 to S-37 and S-12) after injection into PBS and incubationat 37° C. for 2 hours. After the 2 hour-incubation, the non-surfacetreated microparticles (NSTMP), S-27, became dispersed when the testtube was placed on an orbital shaker at 400 rpm for 30 seconds, whilethe surface treated microparticles (STMP), S-28 to S-37 and S-12,remained aggregated under the same agitation condition. Samples fromleft to right, top row to bottom row are S-28, S-29, S-30, S-31, S-32,S-33, S-34, S-35, S-36, S-37, S-12 and S-27 (Example 10).

FIG. 18 illustrates the aggregation of surface treated microparticles(STMP) (S-39 to S-45) after injection into PBS and incubation at 37° C.for 2 hours. After the 2 hour-incubation, the non-surface treatedmicroparticles (NSTMP), S-38, became dispersed when the test tube wasplaced on an orbital shaker at 400 rpm for 30 seconds, while the surfacetreated microparticles (STMP), S-39 to S-45, remained aggregated underthe same agitation condition. Samples from left to right, top row tobottom row are S-39, S-40, S-41, S-42, S-43, S-44 and S-45 (Example 10).

FIG. 19 is a graph depicting PK after a single IVT injection of STMPcontaining 1 mg sunitinib malate in rabbits. The rabbits were sacrificedat 10 days and 3 months and sunitinib levels (ng/g) were determined inthe vitreous, retina, and RPE-Choroid. Sunitinib levels were above theK_(i) for sunitinib against VEGFR and PDGFR in the RPE-Choroid andretina (Example 29). The x-axis represents time post-dose in moths andthe y-axis represents the concentration of sunitinib measured in ng/g.

FIG. 20A is a schematic representation of the locking mechanism of theVacLock syringe highlighting the locking fins and stopping pin asdescribed in Example 31A.

FIG. 20B is a schematic representation of the VacLock syringe when theapparatus is being used for normal sliding use. The stopping pin ispositioned in such a way that the pin does not make contact with alocking fin as described in Example 31A.

FIG. 20C is a schematic representation of the VacLock syringe when theapparatus is capable of being locked to hold vacuum. The stopping pin ispositioned to make contact with the locking fins as described in Example31A.

FIG. 21 is an image of a 60 mL VacLok syringe attached to a suspensionvial through a vial adapter as described in Example 31A. The syringeplunger is locked at 50 mL to create a pressure of approximately 40 Torrinside the vial. The parts of the apparatus are as follows: 1) syringeplunger, which can be locked in different positions to create differentpressures inside the glass vial; 2) 60 mL lockable syringe; 3) vialadapter; and, 4) 2 mL glass vial containing the particle suspension.

FIG. 22A is an image depicting the effect of vacuum treatment asdescribed in Example 31A. The image was taken following the injection ofparticles into 37° C. phosphate buffered saline solution (PBS). Comparedto the FIG. 22B, the microparticles floated following injection.

FIG. 22B is an image depicting the effect of vacuum treatment asdescribed in the optimized procedure of Example 31B. The image was takenfollowing the injection of particles into 37° C. phosphate bufferedsaline solution (PBS). Compared to FIG. 22A, microparticle floatationwas reduced.

FIG. 22C is a comparison of microparticles subjected to the vacuumprocedure of Example 31A (left) and the optimized vacuum procedure ofExample 31B (right). The images were taken following the injection ofparticles into 37° C. phosphate buffered saline solution (PBS).Microparticles subjected to the optimized procedure were less dispersedcompared to the particles subjected to the procedure in Example 31A.

FIG. 23A is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle floatation during injection. Theimage was taken during the injection of particles into a glass tubecontaining 37° C. phosphate buffered saline solution (PBS).

FIG. 23B is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle floatation during injection. Theimage was taken during the injection of particles into a glass tubecontaining 37° C. phosphate buffered saline solution (PBS). Theparticles had been subjected to vacuum treatment for 10 minutes at 143Torr prior to injection.

FIG. 23C is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle floatation during injection. Theimage was taken during the injection of particles into a glass tubecontaining 37° C. phosphate buffered saline solution (PBS). Theparticles had been subjected to vacuum treatment for 10 minutes at 87Torr prior to injection.

FIG. 23D is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle floatation during injection. Theimage was taken during the injection of particles into a glass tubecontaining 37° C. phosphate buffered saline solution (PBS). Theparticles had been subjected to vacuum treatment for 10 minutes at 32Torr prior to injection.

FIG. 23E is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle floatation 10 seconds afterinjection. The image was taken after the injection of particles into aglass tube containing 37° C. phosphate buffered saline solution (PBS).The particles had not been subjected to vacuum treatment prior toinjection (no vacuum was pulled, but the pressure in the vial attachedto the VacLock syringe was approximately 550 Torr due to the slightvacuum introduced before vial capping).

FIG. 23F is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle floatation 10 seconds afterinjection. The image was taken after the injection of particles into aglass tube containing 37° C. phosphate buffered saline solution (PBS).The particles had been subjected to vacuum treatment for 10 minutes at143 Torr prior to injection.

FIG. 23G is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle floatation 10 seconds afterinjection. The image was taken after the injection of particles into aglass tube containing 37° C. phosphate buffered saline solution (PBS).The particles had been subjected to vacuum treatment for 10 minutes at87 Torr prior to injection.

FIG. 23H is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle floatation 10 seconds afterinjection. The image was taken after the injection of particles into aglass tube containing 37° C. phosphate buffered saline solution (PBS).The particles had been subjected to vacuum treatment for 10 minutes at32 Torr prior to injection.

FIG. 23I is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle aggregation. The image was takenafter particles were allowed to incubate for 2 hours in a glass tubecontaining 37° C. phosphate buffered saline solution (PBS) and theparticles were detached from the bottom of the glass by gently tapping.The particles had not been subjected to vacuum treatment prior toinjection (no vacuum was pulled, but the pressure in the vial attachedto the VacLock syringe was approximately 550 Torr due to the slightvacuum introduced before vial capping).

FIG. 23J is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle aggregation. The image was takenafter particles were allowed to incubate for 2 hours in a glass tubecontaining 37° C. phosphate buffered saline solution (PBS) and theparticles were detached from the bottom of the glass by gently tapping.The particles had been subjected to vacuum treatment for 10 minutes at143 Torr prior to injection.

FIG. 23K is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle aggregation. The image was takenafter particles were allowed to incubate for 2 hours in a glass tubecontaining 37° C. phosphate buffered saline solution (PBS) and theparticles were detached from the bottom of the glass by gently tapping.The particles had been subjected to vacuum treatment for 10 minutes at87 Torr prior to injection.

FIG. 23L is an image depicting the effect of vacuum treatment asdescribed in Example 32 on particle aggregation. The image was takenafter particles were allowed to incubate for 2 hours in a glass tubecontaining 37° C. phosphate buffered saline solution (PBS) and theparticles were detached from the bottom of the glass by gently tapping.The particles had been subjected to vacuum treatment for 10 minutes at32 Torr prior to injection.

FIG. 24A is an image depicting the effect of particle concentration onvacuuming outcome as described in Example 33. The image was taken afterparticles (200 mg/mL) were injected into a glass tube containing 37° C.phosphate buffered saline solution (PBS) following vacuuming treatmentfor 20 minutes at approximately 30 Torr. In the image, as measured byvisual assessment, less than 5% of the particles floated.

FIG. 24B is an image depicting the effect of particle concentration onvacuuming outcome as described in Example 33. The image was taken afterparticles (400 mg/mL) were injected into a plastic tube containing 37°C. phosphate buffered saline solution (PBS) following vacuumingtreatment for 20 minutes at approximately 30 Torr. In the image, asmeasured by visual assessment, approximately 40% of the particlesfloated.

FIG. 25A is an image depicting the effect of vacuum treatment time onparticle floatation as described in Example 34. The image was takenafter particles (400 mg/mL) were injected into a plastic tube containing37° C. phosphate buffered saline solution (PBS) following vacuumingtreatment for 10 minutes at approximately 30 Torr. In the image, asmeasured by visual assessment, approximately 20% of the particlesfloated.

FIG. 25B is an image depicting the effect of vacuum treatment time onparticle floatation as described in Example 34. The image was takenafter particles (400 mg/mL) were injected into a plastic tube containing37° C. phosphate buffered saline solution (PBS) following vacuumingtreatment for 30 minutes at approximately 30 Torr. In the image, asmeasured by visual assessment, approximately 8% of the particlesfloated.

FIG. 26A is an image depicting the effect of vacuum treatment onparticle floatation as described in Example 35. The image was takenafter particles (400 mg/mL) were injected into a plastic tube containing37° C. phosphate buffered saline solution (PBS) following high vacuumingtreatment for 10 minutes at approximately 35 Torr.

FIG. 26B is an image depicting the effect of vacuum treatment onparticle floatation as described in Example 35. The image was takenafter particles (400 mg/mL) were injected into a plastic tube containing37° C. phosphate buffered saline solution (PBS) following low vacuumingtreatment for 10 minutes at approximately 550 Torr.

FIG. 27A is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining phosphate buffered saline solution (PBS) followinglyophilization in 1% sucrose.

FIG. 27B is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining phosphate buffered saline solution (PBS) followinglyophilization in 10% sucrose.

FIG. 27C is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining HA solution (5 mg/mL) following lyophilization in 1% sucrose.

FIG. 27D is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining HA solution (5 mg/mL) following lyophilization in 10%sucrose.

FIG. 27E is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining phosphate buffered saline solution (PBS) followinglyophilization in 1% mannitol.

FIG. 27F is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining phosphate buffered saline solution (PBS) followinglyophilization in 10% mannitol.

FIG. 27G is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining HA solution (5 mg/mL) following lyophilization in 1%mannitol.

FIG. 27H is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining HA solution (5 mg/mL) following lyophilization in 10%mannitol.

FIG. 27I is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining HA solution (5 mg/mL) following lyophilization in 1%trehalose.

FIG. 27J is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining HA solution (5 mg/mL) following lyophilization in 10%trehalose.

FIG. 27K is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining phosphate buffered saline solution (PBS) without anylyophilization pre-treatment.

FIG. 27L is an image depicting the effects of excipient type andconcentration on particle floatation as described in Example 36. Theimage was taken after particles were injected into a glass tubecontaining HA solution (5 mg/mL) without any lyophilizationpre-treatment.

FIG. 28 is an image depicting the effects of excipient type andconcentration on particle aggregation as described in Example 36. Theimage was taken after particles were allowed to incubate for 2 hours ina glass tube containing phosphate buffered saline solution (PBS) and theparticles were detached from the bottom of the glass by gently tapping.Prior to injection, the particles were subjected to lyophilization inmannitol, sucrose, or trehalose solution. Particles with excipientsaggregated, while the control had poor aggregation. Excipient solutionsfor lyophilization (in order from left to right) included 10% mannitol,10% sucrose, 10% trehalose, 1% sucrose, 10% sucrose, and control.

FIG. 29A is an image depicting the effect of sonication on particlefloatation as described in Example 37. The image was taken afterparticles suspended in HA were injected into a glass tube containing PBSsolution before the particles were sonicated.

FIG. 29B is an image depicting the effect of sonication on particlefloatation as described in Example 37. The image was taken afterparticles suspended in HA were injected into a glass tube containing PBSsolution after the particles were sonicated.

FIG. 30 is an image depicting the effect of sonication on particleaggregation as described in Example 37. The image was taken afterparticles suspended in HA were allowed to incubate for 2 hours in aglass tube containing phosphate buffered saline solution (PBS) and theparticles were detached from the bottom of the glass by gently tapping.Sample 1 in an image of particle aggregation when the particles were notsubjected to sonication prior to incubation in PBS. Sample 2 is an imageof particle aggregation when the particles were subjected to sonicationprior to incubation in PBS. Aggregation was improved when particles werepre-treated with sonication.

FIG. 31 is a graft depicting the in vitro drug release profiledetermined at 37° C. of the compounds of Table 13 in Example 38. Thex-axis is time measured in days and the y-axis is cumulative releasepercent.

FIG. 32 is a graft depicting the in vitro drug release profile of themicroparticles Table 14 at 37° C. as described in Example 38. The x-axisis time measured in days and the y-axis is cumulative release percent.

FIG. 33 is a graft depicting the in vitro drug release profile of themicroparticles Table 15 at 37° C. as described in Example 38. The x-axisis time measured in days and the y-axis is cumulative release percent.

FIG. 34 is a graft depicting the in vitro drug release profile at 37° C.of the microparticles SM60, SM72, a 7:3 blend of SM60 and SM72, and a7:3 blend of SM79 and SM78 as described in Example 38. The x-axis istime measured in days and the y-axis is cumulative release percent.

FIG. 35 is a graft depicting the in vitro drug release profile of themicroparticles SM90, SM91, SM92, and SM93 as described in Table 18A andTable 18B as described in Example 38. SM 72 is also shown forcomparison. The x-axis is time measured in days and the y-axis iscumulative release percent.

FIG. 36 is a graft depicting the in vitro drug release profile of themicroparticles SM94, SM61, and SM93 as described in Table 19A and Table19B as described in Example 38. The x-axis is time measured in days andthe y-axis is cumulative release percent.

FIG. 37 is a graft depicting the in vitro drug release profile ofmicroparticle blends as described in Example 39. The x-axis is timemeasured in days and the y-axis is cumulative release percent.

FIG. 38 is a graph depicting the in vivo release of the microparticlesSM72, SM60, and a 7:3 mass ratio blend of SM60 and SM72 in a rabbitvitreous after a single intravitreal injection as described in Example40. The x-axis is time measured in months and the y-axis is cumulativerelease percent.

FIG. 39A is a graph depicting the in vivo release profile of themicroparticles SM72, SM60, and a 7:3 mass ratio blend of SM60 and SM72in a rabbit RPE-Choroid as described in Example 40. The x-axis is timemeasured in months and the y-axis is the level of sunitinib (ng/g).

FIG. 39B is a graph depicting in vivo release profile of themicroparticles SM72, SM60, and a 7:3 mass ratio blend of SM60 and SM72in a rabbit retina as described in Example 40. The x-axis is timemeasured in months and the y-axis is the level of sunitinib (ng/g).

FIG. 40A is a graph depicting the sunitinib levels in the central retinaand the RPE/choroid area following dosing with SM74, SM75, and SM76 asdescribed in Example 40. The x-axis is time measured in days and they-axis is the level of sunitinib (ng/g).

FIG. 40B is a graph depicting the remaining sunitinib encapsulated inparticles after dosing with SM74, SM75, and SM76 as described in Example40. The x-axis is time measured in days and the y-axis is sunitinibremaining measured in percent.

DETAILED DESCRIPTION

The present invention has at least the following aspects:

-   -   (i) A lyophilized or otherwise reconstitutable microparticle        composition that has less propensity to result in floating        microparticles than the same microparticle composition that has        not been processed as described herein, when resuspended in        fluid, such as including but not limited to buffered aqueous        solution or aqueous hyaluronic acid, for in vivo delivery. The        process as described herein is based on the discovery that very        small air bubbles or gas or a thin layer of air adhered to        microparticles can adversely affect the quality of the        resuspended microparticle of the present invention, and that        improved microparticles for lyophilization can be provided by        removing adhered air or gas by treating the microparticles with        a vacuum, sonication, or excipient addition or other method that        removes or decreases the adhered air or gas prior to        lyophilization, or by doing so after resuspending the        lyophilized microparticle material. It has been discovered that        the issue of air adhered to the microparticle can be more        pronounced if the microparticle has been surface treated even        under mild conditions to remove or decrease surface surfactant,        such as those described in U.S. Ser. No. 15/349,985 and        PCT/US16/61706 (see nonlimiting Example 2 below).    -   (ii) An improved lyophilized microparticle, microparticle        suspension, and method for manufacture thereof, processed as        described in (i) that is loaded with a pharmaceutically active        agent, including those listed below, which can be active in the        form delivered or is a prodrug, with non-limiting examples        provided herein, for in vivo treatment of a patient in need        thereof.    -   (iii) Microparticles as described herein, and lyophilized or        suspended materials thereof, whether treated to remove adhered        air or gas, and which include any of the active drugs, including        prodrugs, described herein.

For example, it has been identified that for certain applications, theprocesses and materials in U.S. Ser. No. 15/349,985 and PCT/US16/61706provide acceptable aggregating microparticles in vivo, however, thereare occasions when if surface-treated microparticles are overtreated(e.g., treated under strong chemical conditions or for an extendedperiod of time), they may have a tendency to float upon injection intoan aqueous solution with low viscosity (e.g., PBS buffer solution orsometimes vitreal fluid, wherein the viscosity may decrease with age ofthe patient), which can be disadvantageous for forming a pellet thatremains out of the visual axis. Since ocular disorders increase withage, it is important to provide a particle suspension that stillaggregates to a pellet in lower viscosity vitreous fluid. Certainaspects of this invention address those certain situations, where a thinlayer of air, air bubbles or gas generally can adhere to the surface ofsome microparticles and prevent the particles from being completelywetted. If this tiny layer of air or bubbles is high enough to createbuoyancy, the microparticles will be less likely to aggregate to thedesired pellet.

Thus, according to the present invention, microparticles andmicroparticle suspensions are provided that have improved aggregation toa pellet for medical therapy due to enhanced wettability in vivo.Examples of processes that provide improved aggregation of particles tothe desired ocular pellet include, but are not limited to, one or acombination of 1) applying a vacuum to the particle suspension tofacilitate the disassociation of air from particles; 2) adding one ormore excipients to reduce surface hydrophobicity of particles and thusreduce the amount of air adhering to the particles; and, 3) sonicationto facilitate the disassociation of air from the particles, either priorto lyophilization or other drying means to make a solid reconstitutablemicroparticle material, or by carrying out one or more of theseprocesses after reconstitution. These processes are described in moredetail below.

In the third independent aspect of the invention, solid microparticlesthat aggregate in vivo to a pellet and provide release of a therapeuticagent in vivo are provided. In certain embodiments, the therapeuticagent is a lipophilic prodrug as described herein. In certainembodiments, the lipophilic prodrug releases a prostaglandin, carbonicanhydrase inhibitor, receptor tyrosine kinase inhibitor (RTKIs), Rhokinase (ROCK) inhibitor, beta-blocker, alpha-adrenergic agonist, or loopdiuretic. In certain embodiments, the therapeutic agent is the activeagent itself not in prodrug form, such as a prostaglandin, a carbonicanhydrase inhibitor, a receptor tyrosine kinase inhibitor (RTKIs), a Rhokinase (ROCK) inhibitor, a beta-blocker, an alpha-adrenergic agonists,or a loop diuretic. Nonlimiting examples of prodrugs and active agentsthat can be used in the present invention are provided herein. Forexample, one or more of the processes can be used at the time theparticles are being prepared to produce the powder or material that isstored and then later resuspended (for example, prior to lyophilization)for injection. In one example, the vessel with the dried microparticlescan be placed under pressure for storage before use. In anothernon-limiting example, the container storing the surface-treatedmicroparticles can be placed under vacuum directly beforeadministration. In other embodiments, it is not necessary to remove airor gas from the active-loaded microparticle at any stage of manufactureto achieve a suitable therapeutic effect.

In typical embodiments of invention (i) above, the process to preparethe improved suspension for medical use, including for administrationinto low viscosity fluids, is conducted following mild surfacetreatment, isolation, and reconstitution in an appropriate diluent.Non-limiting illustrations in Examples 32-37 establish that treatmentsto provide an improved suspension of microparticles upon injection in anaqueous solution result in less floatation and better aggregationcompared to microparticles that have not been treated for enhancedwettability. FIGS. 22A-22C and 23A-23L illustrate the effect of vacuumstrength on particle floatation and aggregation, and FIGS. 27A-27Lillustrate the effect of excipient addition on particle floatation andaggregation. FIGS. 29A, 29B and 30 depict the effect of sonication onparticle floatation and aggregation.

In one embodiment of a selected aspect of the invention, themicroparticles are mildly surface treated prior to treatments forenhanced wettability. In one embodiment, the solid biodegradablemicroparticles are suitable for ocular injection, at which point theparticles aggregate to form a pellet that remains outside the visualaxis so as not to significantly impair vision. The particles canaggregate into one or several pellets. The size of the aggregate dependson the concentration and volume of the microparticle suspensionsinjected and the diluent in which the microparticles are suspended.

In one aspect of the invention, the improved process of (i) forpreparing a microparticle or lyophilized or otherwise solidifiedmaterial thereof or a suspension thereof, leading to an aggregatedpellet in vivo, can be used in combination with a selected method andfor forming aggregating microparticles described in U.S. Ser. No.15/349,985 and PCT/US16/61706 (and the resulting materials thereof). Forexample, methods include providing solid aggregating microparticles thatinclude at least one biodegradable polymer, wherein the solidaggregating microparticles have a solid core, include a therapeuticagent, have a modified surface which has been treated under mildconditions at a temperature, that may optionally be at or less thanabout 18° C., to remove surface surfactant, are sufficiently small to beinjected in vivo, and are capable of aggregating in vivo to form atleast one pellet of at least 500 μm in vivo to provide sustained drugdelivery in vivo for at least three months, four months, five months,six months seven months, eight months, nine months or more. In certainembodiments, sustained drug deliver in vivo is provided for up to oneyear. The solid aggregating microparticles are suitable, for example,for an intravitreal injection, implant, including an ocular implant,periocular delivery, or delivery in vivo outside of the eye. In certainembodiments, the therapeutic agent is a prodrug as described herein.

As an illustration, the present invention includes a process for thepreparation of surface-modified solid aggregating microparticles thatare advantageous for pellet formation in vivo, and microparticlematerials made thereby, that includes:

-   -   A. a first step of preparing microparticles comprising one or        more biodegradable polymers by dissolving or dispersing the        polymer(s) and a therapeutic agent in one or more solvents to        form a polymer and therapeutic agent solution or dispersion,        mixing the polymer and the therapeutic agent solution or        dispersion with an aqueous phase containing a surfactant to        produce solvent-laden microparticles and then removing the        solvent(s) to produce polymer microparticles that contain the        therapeutic agent, polymer and surfactant; and    -   B. a second step of mildly treating the surface of        microparticles of step (i) at a temperature at or below about        18, 15, 10, 8 or 5° C. optionally up to about 1, 2, 3, 4, 5, 10,        30, 40, 50, 60, 70, 80, 90 100, 11, 120 or 140 minutes with an        agent that removes surface surfactant, surface polymer, or        surface oligomer in a manner that does not significantly produce        internal pores; and    -   C. isolating the surface treated microparticles; and    -   D. subjecting the microparticles to at least one process        selected from 1) vacuum treatment prior to lyophilization or        other form of reconstitutable solidification, or after the step        of reconstitution wherein the microparticles are suspended in a        diluent and the suspension is placed under vacuum prior to        use; 2) excipient addition, wherein an excipient is added prior        to lyophilization; and 3) sonication, prior to lyophilization or        other form of reconstitutable solidification, or after the step        of reconstitution; 4) sealing the vial containing the dry powder        of particles under vacuum, including but not limited to high        vacuum; or 5) pre-wetting (i.e., resuspending) the        surface-treated microparticles in a diluent for 2-24 hours        before injecting into the eye, for example in a hyaluronic acid        solution or other sterile solution suitable for ocular        injection.

The process of these steps can be achieved in a continuous manufacturingline or via one step or in step-wise fashion as appropriate. The processof step D. above can be carried out following isolation of themicroparticles and/or upon reconstitution prior to injection. In oneembodiment, the surface treated solid biodegradable microparticles donot significantly aggregate during the manufacturing process. In anotherembodiment, the surface treated solid biodegradable microparticles donot significantly aggregate when resuspended and loaded into a syringe.In some embodiments, the syringe is approximately 30, 29, 28, 27, 26 or25 gauge, with either normal or thin wall.

In another nonlimiting embodiment, a process for preparing a suspensioncomprising a microparticle and a pharmaceutically active compoundencapsulated in the microparticle and the resulting materials thereof;which process comprises:

-   -   (i) preparing a solution or suspension (organic phase)        comprising: (i) PLGA or PLA or PLA and PLGA, (ii) PLGA-PEG or        PLA-PEG (iii) a pharmaceutically active compound, for example,        as described herein and (iv) one or more organic solvents;    -   (j) preparing an emulsion in an aqueous polyvinyl alcohol (PVA)        solution (aqueous phase) by adding the organic phase into the        aqueous phase and mixing them until particle formation (for        example at about 3,000 to about 10,000 rpm for about 1 to about        30 minutes);    -   (k) removing additional solvent as necessary using known        techniques;    -   (l) centrifuging or causing the sedimentation of the        microparticle that is loaded with a pharmaceutically active        compound or prodrug thereof;    -   (m) optionally removing additional solvent and/or washing the        microparticle loaded with the pharmaceutically active compound        or prodrug thereof with water;    -   (n) filtering the microparticle loaded with pharmaceutically        active compound or prodrug thereof to remove aggregates or        particles larger than the desired size;    -   (o) optionally lyophilizing the microparticle comprising the        pharmaceutically active compound and storing the microparticle        as a dry powder in a manner that maintains stability for up to        about 6, 8, 10, 12, 20, 22, or 24 months or more; and    -   (p) optionally improving the aggregation potential of the        particles by subjecting the particles to at least one process        selected from 1) vacuum treatment prior to step (g), or after        reconstitution wherein the microparticles are suspended in a        diluent and the suspension is placed under vacuum; 2) excipient        addition, wherein an excipient is added prior to lyophilization;        and 3) sonication prior to step (g), or during reconstitution        wherein the microparticles are suspended in a diluent and        sonicated; 4) sealing the vial containing the dry powder of        particles under vacuum, including but not limited to high        vacuum; or 5) pre-wetting (i.e., resuspending) the        surface-treated microparticles in a diluent for 2-24 hours        before injecting into the eye, for example in a hyaluronic acid        solution or other sterile solution suitable for ocular        injection.

In one embodiment, a process for preparing an improved lyophilizedmaterial or a suspension of microparticles following reconstitutionincludes suspending the particles in a diluent and subjecting theparticles to vacuum treatment at a pressure of about less than about500, 400, 300, 200, 150, 100, 75, 50, 40, 35, 34, 33, 32, 31, 30, 29, 28or 25 Torr for a suitable amount of time to substantially remove airattached to the particles, which in some embodiments can be up to 3, 5,8, 10, 20, 30, 40, 50, 60, 70, 80, or 90 minutes or up to 2, 3, 4, 5, or6, 10, 15 or 24 or more hours. In one embodiment, the vacuum treatmentis conducted with a VacLock syringe in a size of up to at least 10, 20,30, or 60 mL.

In certain non-limiting embodiments, the microparticles are vacuumed ata strength of less than 40 Torr for about 3, 5, 8, 10, 20, 30, 45, 60,75, or 90 minutes. In certain non-limiting embodiments, themicroparticles are vacuumed at a strength less than 40 Torr from about 1to 90 minutes, from about 1 to 60 minutes, from about 1 to 45 minutes,from about 1 to 30 minutes, from about 1 to 15 minutes, or from about 1to 5 minutes.

In certain embodiments, the diluent for suspending particles is ProVisc.In some embodiments, the microparticles are diluted from about 10-foldto about 40-fold, from about 15-fold to about 35-fold, or from about20-fold to about 25-fold. In some embodiments, the diluent forsuspending particles is a 10×-diluted ProVisc (0.1% HA in PBS) solution,a 20×-diluted ProVisc (0.05% HA in PBS) solution, or a 40×-dilutedProVisc (0.025% HA in PBS) solution. In some embodiment, the particlesare suspended in the diluent at a concentration of at least about 100mg/mL, 200 mg/mL, 300 mg/mL, 400 mg/mL, or 500 mg/mL.

I. Terminology

Although specific terms are employed herein, they are used in a genericand descriptive sense only and not for purposes of limitation. Unlessotherwise defined, all technical and scientific terms used herein havethe same meaning as commonly understood by one of ordinary skill in theart to which this presently described subject matter belongs.

Compounds are described using standard nomenclature. Unless definedotherwise, all technical and scientific terms used herein have the samemeaning as is commonly understood by one of skill in the art to whichthis invention belongs.

The terms “a” and “an” do not denote a limitation of quantity, butrather denote the presence of at least one of the referenced items.

Recitation of ranges of values are merely intended to serve as ashorthand method of referring individually to each separate valuefalling within the range, unless otherwise indicated herein, and eachseparate value is incorporated into the specification as if it wereindividually recited herein. The endpoints of all ranges are includedwithin the range and are independently combinable. All methods describedherein can be performed in a suitable order unless otherwise indicatedherein or otherwise clearly contradicted by context. The use ofexamples, or exemplary language (e.g., “such as”), is intended merely tobetter illustrate the invention and does not pose a limitation on thescope of the invention unless otherwise claimed.

The term “carrier” refers to a diluent, excipient, or vehicle.

A “dosage form” means a unit of administration of a composition thatincludes a surface treated microparticle and a therapeutically activecompound. Examples of dosage forms include injections, suspensions,liquids, emulsions, implants, particles, spheres, creams, ointments,inhalable forms, transdermal forms, buccal, sublingual, topical, gel,mucosal, and the like. A “dosage form” can also include, for example, asurface treated microparticle comprising a pharmaceutically activecompound in a carrier.

The term “microparticle” means a particle whose size is measured inmicrometers (μm). Typically, the microparticle has an average diameterof from about 1 μm to 100 μm. In some embodiments, the microparticle hasan average diameter of from about 1 μm to 60 μm, for instance from about1 μm to 40 μm; from about 10 μm to 40 μm; from about 20 μm to 40 μm;from about 25 μm to 40 μm; from about 25 μm to about 30 μm; from about20 μm to 35 μm. For example, the microparticle may have an averagediameter of from 20 μm to 40 μm, and in certain embodiments, 20, 21, 22,23, 24, 25, 26, 27, 28, 29, 30, 31, 32 or 33. As used herein, the term“microsphere” means a substantially spherical microparticle.

A “patient” or “host” or “subject” is typically a human, however, may bemore generally a mammal. In an alternative embodiment it can refer to,for example, a cow, sheep, goat, horse, dog, cat, rabbit, rat, mouse,bird and the like.

The term “mild” or “mildly” when used to describe the surfacemodification of the microparticles means that the modification(typically the removal of surfactant from the surface, as opposed to theinner core, of the particle) is less severe, pronounced or extensivethan when carried out at room temperature with the otherwise sameconditions. In general, the surface modification of the solidmicroparticles of the present invention is carried out in a manner thatdoes not create significant channels or large pores that wouldsignificantly accelerate the degradation of the microparticle in vivo,yet serves to soften and decrease the hydrophilicity of the surface tofacilitate in vivo aggregation.

The term “solid” as used to characterize the mildly surface treatedmicroparticle means that the particle is substantially continuous inmaterial structure as opposed to heterogeneous with significant channelsand large pores that would undesirably shorten the time ofbiodegradation.

The term “sonicate” means to subject the microparticle suspension toultrasonic vibration, or high frequency sound waves.

II. Processes for Producing Improved Suspensions of Surface-TreatedAggregating Microparticles for Therapeutic Purposes

In one embodiment, the present invention provides processes forproducing suspensions of surface-treated aggregating microparticles fortherapeutic purposes that aggregate in vivo to form pellet(s). Theprocesses include improving the wettability of surface-treatedmicroparticles by removing air or air bubbles from the surface of themicroparticle. The treatment for enhanced wettability is conductedfollowing mild surface treatment, isolation, and reconstitution in anappropriate diluent.

In one embodiment, the invention is thus solid aggregatingmicroparticles treated for improved wettability that include at leastone biodegradable polymer, wherein the surface-modified solidaggregating microparticles have a solid core, include a therapeuticagent, have a modified surface which has been treated under mildconditions at a temperature at or less than about 18° C. to removesurface surfactant or cause surface polymer to partially degrade, havebeen treated by at least one or more processes selected from vacuumtreatment, the addition of an excipient, and sonication to improvewettability upon injection, are sufficiently small to be injected invivo, and aggregate in vivo to form at least one pellet of at least 500μm in vivo in a manner that provides sustained drug delivery in vivo forat least one, two, three, four, five, six or seven months or more. Thesurface modified solid aggregating microparticles are suitable, forexample, for an intravitreal injection, implant, including an ocularimplant, periocular delivery or delivery in vivo outside of the eye.

The present invention further includes a process for the preparation ofsurface-modified solid aggregating microparticles that have also beentreated for enhanced wettability that includes

-   -   (i) a first step of preparing microparticles comprising one or        more biodegradable polymers by dissolving or dispersing the        polymer(s) and a therapeutic agent in one or more solvents to        form a polymer and therapeutic agent solution or dispersion,        mixing the polymer and the therapeutic agent solution or        dispersion with an aqueous phase containing a surfactant to        produce microparticles that contain the therapeutic agent,        polymer and surfactant; and    -   (ii) a second step of mildly treating the surface of        microparticles of step (i) at a temperature at or below about        18, 15, 10, 8 or 5° C. optionally up to about 1, 2, 3, 4, 5, 10,        30, 40, 50, 60, 70, 80, 90 100, 11, 120 or 140 minutes with an        agent that removes surface surfactant, surface polymer, or        surface oligomer in a manner that does not significantly produce        internal pores; and    -   (iii) isolating the surface treated microparticles; and    -   (iv) improving the aggregation potential of the particles by        subjecting the particles to at least one process selected        from 1) vacuum treatment, wherein the microparticles are        suspended in a diluent and the suspension is placed under vacuum        prior to use; 2) excipient addition, wherein an excipient is        added prior to lyophilization; and 3) sonication, wherein the        microparticles are suspended in a diluent and sonicated; 4)        sealing the vial containing the dry powder of particles under        vacuum, including but not limited to high vacuum; or 5)        pre-wetting (i.e., resuspending) the surface-treated        microparticles in a diluent for 2-24 hours before injecting into        the eye, for example in a hyaluronic acid solution or other        sterile solution suitable for ocular injection.

In one embodiment, the surface treatment includes treatingmicroparticles with aqueous base, for example, sodium hydroxide and asolvent (such as an alcohol, for example ethanol or methanol, or anorganic solvent such as DMF, DMSO or ethyl acetate) as otherwisedescribed above. More generally, a hydroxide base is used, for example,potassium hydroxide. An organic base can also be used. In otherembodiments, the surface treatment as described above is carried out inaqueous acid, for example hydrochloric acid. In one embodiment, thesurface treatment includes treating microparticles with phosphatebuffered saline and ethanol.

In some embodiments, the surface treatment is carried out at atemperature of not more than 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16,17 or 18° C., at a reduced temperature of about 5 to about 18° C., about5 to about 16° C., about 5 to about 15° C., about 0 to about 10° C.,about 0 to about 8° C., or about 1 to about 5° C., about 5 to about 20°C., about 1 to about 10° C., about 0 to about 15° C., about 0 to about10° C., about 1 to about 8° C., or about 1 to about 5° C. Eachcombination of each of these conditions is considered independentlydisclosed as if each combination were separately listed.

The pH of the surface treatment will of course vary based on whether thetreatment is carried out in basic, neutral or acidic conditions. Whencarrying out the treatment in base, the pH may range from about 7.5 toabout 14, including not more than about 8, 9, 10, 11, 12, 13 or 14. Whencarrying out the treatment in acid, the pH may range from about 6.5 toabout 1, including not less than 1, 2, 3, 4, 5, or 6. When carrying outunder neutral conditions, the pH may typically range from about 6.4 or6.5 to about 7.4 or 7.5.

A key aspect of the present invention is that the treatment, whetherdone in basic, neutral or acidic conditions, includes a selection of thecombination of the time, temperature, pH agent and solvent that causes amild treatment that does not significantly damage the particle in amanner that forms pores, holes or channels. Each combination of each ofthese conditions is considered independently disclosed as if eachcombination were separately listed.

The treatment conditions should simply mildly treat the surface in amanner that allows the particles to remain as solid particles, beinjectable without undue aggregation or clumping, and form at least oneaggregate particle of at least 500 μm.

In one embodiment, the surface treatment includes treatingmicroparticles with an aqueous solution of pH=6.6 to 7.4 or 7.5 andethanol at a reduced temperature of about 1 to about 10° C., about 1 toabout 15° C., about 5 to about 15° C., or about 0 to about 5° C. In oneembodiment, the surface treatment includes treating microparticles withan aqueous solution of pH=6.6 to 7.4 or 7.5 and an organic solvent at areduced temperature of about 0 to about 10° C., about 5 to about 8° C.,or about 0 to about 5° C. In one embodiment, the surface treatmentincludes treating microparticles with an aqueous solution of pH=1 to 6.6and ethanol at a reduced temperature of about 0 to about 10° C., about 0to about 8° C., or about 0 to about 5° C. In one embodiment, the surfacetreatment includes treating microparticles with an organic solvent at areduced temperature of about 0 to about 18° C., about 0 to about 16° C.,about 0 to about 15° C., about 0 to about 10° C., about 0 to about 8°C., or about 0 to about 5° C. The decreased temperature of processing(less than room temperature, and typically less than 18° C.) assists toensure that the particles are only “mildly” surface treated.

In yet another embodiment, a method for the treatment of an oculardisorder is provided that includes administering to a host in needthereof solid aggregating microparticles described herein that includean effective amount of a therapeutic agent, wherein the solidaggregating microparticles are injected into the eye and aggregate invivo to form at least one pellet of at least 500 μm that providessustained drug delivery for at least approximately one, two, three,four, five, six, seven, eight, nine, ten, eleven, twelve or more monthsin such a manner that the pellet stays substantially outside the visualaxis so as not to significantly impair vision. In one embodiment, thesolid biodegradable microparticles release about 1 to about 20 percent,about 1 to about 15 percent, about 1 to about 10 percent, or about 5 to20 percent, for example, up to about 1, 5, 10, 15 or 20 percent, of thetherapeutic agent over the first twenty-four-hour period.

Vacuum Treatment

In one embodiment, the process for providing an improved microparticlesuspension prior to injection includes vacuum treatment wherein theparticles are suspended in a diluent and subjected to negative pressureto remove unwanted air at the surface of the microparticles. Nonlimitingexamples of the negative pressure can be about or less than 300, 200,100, 150, 145, 143, 90, 89, 88, 87, 86, 85, 75, 50, 35, 34, 33, 32, 31,or 30 Torr for any appropriate time to achieve the desired results,including but not limited to 120, 110, 100, 90, 80, 70, 60, 50, 40, 30,20, 10, 8, 5, or 3 minutes.

In one embodiment, microparticles are stored under negative pressurefollowing the manufacturing and isolation process, wherein negativepressure is defined as any pressure lower than the pressure of ambientroom temperature (approximately 760 Torr). In one embodiment, themicroparticles are stored at a pressure of less than about 700 Torr, 550Torr, 500 Torr, 450 Torr, 400 Torr, 350 Torr, 300 Torr, 250 Torr, 200Torr, 150 Torr, 100 Torr, 90 Torr, 80 Torr, 60 Torr, 40 Torr, 35 Torr,32 Torr, 30 Torr, or 25 Torr following the manufacturing and isolationprocess. In one embodiment, the microparticles are stored at a pressureof about 500 Torr to about 25 Torr following the manufacturing andisolation process. In one embodiment, the microparticles are stored at apressure of about 300 Torr to about 25 Torr following the manufacturingand isolation process. In one embodiment, the microparticles are storedat a pressure of about 100 Torr to about 25 Torr following themanufacturing and isolation process. In one embodiment, themicroparticles are stored at a pressure of about 90 Torr to about 25Torr following the manufacturing and isolation process. In oneembodiment, the microparticles are stored at a pressure of about 50 Torrto about 25 Torr following the manufacturing and isolation process. Inone embodiment, the microparticles are stored at a pressure of about 40Torr to about 25 Torr following the manufacturing and isolation process.In one embodiment, the microparticles are stored at a pressure of about35 Torr to about 25 Torr following the manufacturing and isolationprocess. In a further embodiment, the microparticles are stored at atemperature of between about 2-8° C. at a pressure that is less thanabout 700, 550, 500, 450, 400, 350, 300, 250, 200, 150, 100, 80, 60, 50,40, 35, 32, 30, or 25 Torr.

In one embodiment, the microparticles are stored at pressure for up to 1week, 2 weeks, 3 weeks, 4 weeks, 1 month, 2 months, 3 months, 4 months,or more following the manufacture and isolation process. In oneembodiment, the microparticles are stored for up to 1 week to up to 4weeks at a pressure that is less than 700, 550, 500, 450, 400, 350, 300,250, 200, 150, 100, 80, 60, 50, 40, 35, 32, or 30 Torr. In oneembodiment, the microparticles are stored for up to 1 month to up to 2months at a pressure that is less than 700, 550, 500, 450, 400, 350,300, 250, 200, 150, 100, 80, 60, 50, 40, 35, 32, or 30 Torr. In oneembodiment, the microparticles are stored for up to 3 months at apressure that is less than 700, 550, 500, 450, 400, 350, 300, 250, 200,150, 100, 80, 60, 50, 40, 35, 32, or 30 Torr

In one embodiment, the microparticles are stored at a temperature ofbetween about 2-8° C. following the manufacturing and isolation processand the microparticles are vacuumed less than about 2 hours, 1 hour, 30minutes, 15 minutes, or 10 minutes prior to in vivo injection. In oneembodiment, the microparticles are stored at a temperature of betweenabout 2-8° C. following the manufacturing and isolation process and themicroparticles are vacuumed 1 hour to 30 minutes prior to in vivoinjection. In one embodiment, the microparticles are stored at atemperature of between about 2-8° C. following the manufacturing andisolation process and the microparticles are vacuumed 30 minutes to 10minutes prior to in vivo injection. In one embodiment, themicroparticles are stored at a temperature of between about 2-8° C.following the manufacturing and isolation process and the microparticlesare vacuumed immediately prior to in vivo injection.

In one embodiment, the microparticles are stored at a temperature ofbetween about 2-8° C. and the microparticles are vacuumed for less than1 hour, 30 minutes, 20 minutes, 15 minutes, or 10 minutes at a strengthof less than about 35 Torr immediately prior to in vivo injection. Inone embodiment, the microparticles are stored at a temperature ofbetween about 2-8° C. and the microparticles are vacuumed for 1 hour to30 minutes at a strength of less than about 35 Torr immediately prior toin vivo injection. In one embodiment, the microparticles are stored at atemperature of between about 2-8° C. and the microparticles are vacuumedfor 30 minutes to 10 minutes at a strength of less than about 35 Torrimmediately prior to in vivo injection.

In one embodiment, the particles are suspended in a glass vial that isattached to a vial adapter and the vial adapter is in turn attached to aVacLok syringe (FIG. 21 ). A negative pressure is created in the vial bypulling the plunger of the syringe into a locking position as shown inFIG. 20C. In one embodiment, the vacuum treatment is conducted in asyringe of the 60 mL, 30 mL, 20 mL, or 10 mL size. The vacuum is thenheld in the syringe with the vial facing up and the large syringeattached for up to at least 10 minutes, 20 minutes, 30 minutes, 40minutes, 50 minutes, 60 minutes, 70 minutes, 90 minutes, 100 minutes, or129 minutes. The vacuum is released, the large syringe is detached, anda syringe is attached for in vivo injection.

In one embodiment, the particles are subjected to vacuum treatment at astrength of about 143 Torr for about at least 10 minutes, 20 minutes, 30minutes, 40 minutes, 50 minutes, 60 minutes, 70 minutes, 80 minutes, 90minutes, 100 minutes, or 120 minutes. In one embodiment, the particlesare subjected to vacuum treatment at a strength of at least about 90,89, 88, 87, 86, or 85 Torr for at least about at 10 minutes, 20 minutes,30 minutes, or 40 minutes. In one embodiment, the particles aresubjected to vacuum treatment at a strength of at least about 87 Torrfor at least about 10 minutes, 20 minutes, 30 minutes, 40 minutes, 60minutes, 90 minutes, or 120 minutes. In one embodiment, the particlesare subjected to vacuum treatment at a strength of at least about 35,34, 33, 32, 31, or 30 Torr for at least 5 minutes. In one embodiment,the particles are subjected to vacuum treatment at a strength of atleast about 35, 34, 33, 32, 31, or 30 Torr for at least 8 minutes. Inone embodiment, the particles are subjected to vacuum treatment at astrength of at least about 35, 34, 33, 32, 31, or 30 Torr for at least10 minutes. In one embodiment, the particles are subjected to vacuumtreatment at a strength of at least about 35, 34, 33, 32, 31, or 30 Torrfor at least 20 minutes. In one embodiment, the particles are subjectedto vacuum treatment at a strength of at least about 35, 34, 33, 32, 31,or 30 Torr for at least 30 minutes. In one embodiment, the particles aresubjected to vacuum treatment at a strength of at least about 35, 34,33, 32, 31, or 30 Torr for at least 40 minutes. In one embodiment, theparticles are subjected to 30 Torr for at least 5, 10, 15, 20, 25, 30,35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or 90 minutes. In oneembodiment, the particles are subjected to vacuum treatment at astrength of about 35 Torr for at least 90 minutes. In one embodiment,the particles are subjected to vacuum treatment at a strength of about35 Torr for at least 60 minutes. In one embodiment, the particles aresubjected to vacuum treatment at a strength of about 35 Torr for atleast 30 minutes. In one embodiment, the particles are subjected tovacuum treatment at a strength of about 35 Torr for at least 15 minutes.In one embodiment, the particles are subjected to vacuum treatment at astrength of about 35 Torr for at least 5 minutes. In one embodiment, theparticles are subjected to vacuum treatment at a strength of about 32Torr for at least 30 minutes. In one embodiment, the particles aresubjected to vacuum treatment at a strength of about 32 Torr for atleast 15 minutes. In one embodiment, the particles are subjected tovacuum treatment at a strength of about 32 Torr for at least 5 minutes.In one embodiment, the particles are subjected to vacuum treatment at astrength of about 30 Torr for at least 30 minutes. In one embodiment,the particles are subjected to vacuum treatment at a strength of about30 Torr for at least 15 minutes. In one embodiment, the particles aresubjected to vacuum treatment at a strength of about 30 Torr for atleast 5 minutes.

In an alternative embodiment, the particles are suspended in a diluentin a vial attached to a vial adapter that is further attached to a 60 mLVacLok syringe containing a plunger (as shown in FIG. 21 ) wherein theplunger is pulled to the 50 mL mark and locked to create a negativepressure of approximately 30 Torr and the pressure is held for at leastabout 3, 5, 8, 10, 15, 20, 25, 30, or 35 minutes. In an alternativeembodiment, the particles are suspended in a diluent in a vial attachedto a vial adapter that is further attached to a 60 mL VacLok syringecontaining a plunger wherein the plunger is pulled to the 45 mL mark,locked, and held for at least about 3, 5, 8, 10, 15, 20, 25, 30, 35, 40,45, 50, 55, 60, 65, 70, 75, 80, 85, or 90 minutes. In an alternativeembodiment, the particles are suspended in a diluent in a vial attachedto a vial adapter that is further attached to a 60 mL VacLok syringecontaining a plunger wherein the plunger is pulled to the 40 mL mark,locked, and the pressure is held for at least about 3, 5, 8, 10, 15, 20,25, 30, or 35 minutes. In an alternative embodiment, the particles aresuspended in a diluent in a vial attached to a vial adapter that isfurther attached to a 60 mL VacLok syringe containing a plunger whereinthe plunger is pulled to the 35 mL mark, locked, and held for about atleast 3, 5, 8, 10, 15, 20, 25, 30, or 35 minutes. In an alternativeembodiment, the particles are suspended in a diluent in a vial attachedto a vial adapter that is further attached to a 60 mL VacLok syringecontaining a plunger wherein the plunger is pulled to the 30 mL mark,locked, and held for at least about 3, 5, 8, 10, 15, 20, 25, 30, or 35minutes. In an alternative embodiment, the particles are suspended in adiluent in a vial attached to a vial adapter that is further attached toa 60 mL VacLok syringe containing a plunger wherein the plunger ispulled to the 25 mL mark, locked, and held for at least about 3, 5, 8,10, 15, 20, 25, 30, or 35 minutes.

In certain embodiments, the particles are suspended in a diluent and thesuspension is exposed to a pressure of less than 40 Torr for betweenabout 90 minutes and 1 minute, between about 60 minutes and 1 minute,between about 45 minutes and 1 minute, between about 30 minutes and 1minute, between about 15 minutes and 1 minute, or between about 5minutes and 1 minute.

In certain embodiments, the particles are suspended in a diluent and thesuspension is exposed to a pressure of less than 30 Torr for betweenabout 90 minutes and 1 minute, between about 60 minutes and 1 minute,between about 45 minutes and 1 minute, between about 30 minutes and 1minute, between about 15 minutes and 1 minute, or between about 5minutes and 1 minute.

In one embodiment, the microparticles are suspended in a diluent of 10×ProVisc-diluted (0.1% HA in PBS) solution. In one embodiment, themicroparticles are suspended in a diluent of 20×-diluted ProVisc (0.05%HA in PBS). In one embodiment, the microparticles are suspended in adiluent of 40×-diluted ProVisc (0.025% HA in PBS).

In one embodiment, the particles are suspended in the diluent at aconcentration of 100 mg/mL, 150 mg/mL, 200 mg/mL, 250 mg/mL, 300 mg/mL,350 mg/mL, 400 mg/mL, 450 mg/mL or 500 mg/mL. In one embodiment, theparticles are suspended in 10×-diluted ProVisc (0.1% HA in PBS) solutionand the suspension has a final concentration of 200 mg/mL. In oneembodiment, the particles are suspended in 10×-diluted ProVisc (0.1% HAin PBS) solution and the suspension has a final concentration of 400mg/mL. In one embodiment, the particles are suspended in a 20×-dilutedProVisc (0.05% HA in PBS) and the suspension has a final concentrationof 200 mg/mL. In one embodiment, the particles are suspended in a20×-diluted ProVisc (0.05% HA in PBS) and the suspension has a finalconcentration of 400 mg/mL. In one embodiment, the particles aresuspended in a 40×-diluted ProVisc (0.025% HA in PBS) and the suspensionhas a concentration of 200 mg/mL. In one embodiment, the particles aresuspended in a 40×-diluted ProVisc (0.025% HA in PBS) and the suspensionhas a concentration of 400 mg/mL.

The Addition of an Excipient

In one embodiment, the process for preparing an improved microparticlesuspension prior to injection is the addition of at least one excipient,typically prior to lyophilization that reduces the amount of airadhering to the particles. Particles are suspended in an aqueoussolution and sonicated before being flash frozen in −80° C. ethanol andlyophilized overnight. In one embodiment, the particles are suspended inan aqueous sugar solution that is 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%,10%, 11%, 12%, 13%, 14%, or 15% sugar. In one embodiment, the sugar issucrose. In one embodiment, the sugar is mannitol. In one embodiment,the sugar is trehalose. In one embodiment, the sugar is glucose. In oneembodiment, the sugar is selected from arabinose, fucose, mannose,rhamnose, xylose, D-xylose, glucose, fructose, ribose, D-ribose,galactose, dextrose, dextran, lactose, maltodextrin, maltose, glycerol,erythritol, threitol, arabitol, xylitol, ribitol, sorbitol, galactitol,fucitol, iditol, inositol, volemitol, isomalt, maltitol, lactitol,maltotriitol, maltotetraitol, and polyglycitol. In an alternativeembodiment, the sugar is selected from aspartame, saccharin, stevia,sucralose, acesulfame potassium, advantame, alitame, neotame, andsucralose. In one embodiment, the particles are suspended in an aqueoussugar solution that is 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%,12%, 13%, 14%, or 15% sucrose. In one embodiment, the particles aresuspended in a 1% sucrose solution. In one embodiment, the particles aresuspended in a 10% sucrose solution. In one embodiment, the particlesare suspended in an aqueous sugar solution that is 1%, 2%, 3%, 4%, 5%,6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, or 15% mannitol. In oneembodiment, the particles are suspended in a 1% mannitol solution. Inone embodiment, the particles are suspended in a 10% mannitol solution.In one embodiment, the particles are suspended in a 1% trehalosesolution. In one embodiment, the particles are suspended in a 10%trehalose solution. In one embodiment, the particles are suspended in anaqueous sugar solution that is 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%,11%, 12%, 13%, 14%, or 15% trehalose. In an alternative embodiment, theparticles are suspended in a small surfactant molecule, including, butnot limited to tween 20 or tween 80. In an alternative embodiment, theparticles are flash frozen in −80° C. methanol or isopropanol.

Sonication

In one embodiment, a process for providing an improved microparticlesuspension prior to injection is sonication wherein particles aresuspended in a diluent and the suspension of microparticles is sonicatedfor at least 30 minutes, at least 25 minutes, at least 20 minutes, atleast 15 minutes, at least 10 minutes, at least 8 minutes, at least 5minutes, or at least 3 minutes. In one embodiment, the particlesolutions are sonicated at a frequency of 40 kHz. In one embodiment, theparticles are suspended in the diluent at a concentration of 100 mg/mL,150 mg/mL, 200 mg/mL, 250 mg/mL, 300 mg/mL, 350 mg/mL, 400 mg/mL, 450mg/mL or 500 mg/mL. In one embodiment, the diluent is hyaluronic acid.In an alternative embodiment, the diluent is selected from hyaluronicacid, hydroxypropyl methylcellulose, chondroitin sulfate, or a blend ofat least two diluents selected from hyaluronic acid, hydroxypropylmethylcellulose, and chondroitin sulfate. In an alternative embodiment,the diluent is selected from aacia, tragacanth, alginic acid,carrageenan, locust bean gum, gellan gum, guar gum, gelatin, starch,methylcellulose, sodium carboxymethylcellulose, hydroxyethylcellulose,hydroxypropyl cellulose, Carbopol® homopolymers (acrylic acidcrosslinked with allyl sucrose or allyl pentaerythritol), and Carbopol®copolymers (acrylic acid and C₁₀-C₃₀ alkyl acrylate crosslinked withallyl pentaerythritol).

In certain embodiments, a combination of vacuum treatment, the additionof excipients, and sonication can be used following isolation andreconstitution of the microparticles. In certain embodiments, themethods for enhancing wettability are conducted at least 1 hour prior toin vivo injection, at least 45 minutes prior to in vivo injection, atleast 30 minutes prior to in vivo injection, at least 25 minutes priorto in vivo injection, at least 20 minutes prior to injection, at least15 minutes prior to in vivo injection, at least 10 minutes prior to invivo injection, or at least 5 minutes prior to in vivo injection. In oneembodiment, the vacuum treatment, addition of an excipient, and/orsonication is conducted immediately before in vivo injection. In oneembodiment, the particles are vacuumed at a strength of less than 35Torr for less than 30 minutes and are immediately injected in vivo. Inan alternative embodiment, the particles are vacuumed at a strength ofless than 35 Torr for less than 20 minutes and are immediately injectedin vivo. In an alternative embodiment, the particles are vacuumed at astrength of less than 35 Torr for less than 15 minutes and areimmediately injected in vivo. In an alternative embodiment, theparticles are vacuumed at a strength of less than 35 Torr for less than10 minutes and are immediately injected in vivo.

In one embodiment, the microparticles are stored at a temperature ofbetween about 2-8° C. following the manufacturing and isolation processand the microparticles are held under negative pressure for about 24,12, 8, 6, 2 hours, 1 hour, 30 minutes, 15 minutes, or 10 minutes or lessprior to in vivo injection. In one embodiment, the microparticles arestored at a temperature of between about 2-8° C. following themanufacturing and isolation process and the microparticles are heldunder negative pressure 1 hour to 30 minutes prior to in vivo injection.In one embodiment, the microparticles are stored at a temperature ofbetween about 2-8° C. following the manufacturing and isolation processand the microparticles are vacuumed 30 minutes to 10 minutes prior to invivo injection. In one embodiment, the microparticles are stored at atemperature of between about 2-8° C. following the manufacturing andisolation process and the microparticles are vacuumed immediately priorto in vivo injection.

In one embodiment, the microparticles are stored at a temperature ofbetween about 2-8° C. and the microparticles are vacuumed for less than1 hour, 30 minutes, 20 minutes, 15 minutes, or 10 minutes at a strengthof less than about 35 Torr immediately prior to in vivo injection. Inone embodiment, the microparticles are stored at a temperature ofbetween about 2-8° C. and the microparticles are vacuumed for 1 hour to30 minutes at a strength of less than about 35 Torr immediately prior toin vivo injection. In one embodiment, the microparticles are stored at atemperature of between about 2-8° C. and the microparticles are vacuumedfor 30 minutes to 10 minutes at a strength of less than about 35 Torrimmediately prior to in vivo injection.

In one embodiment, the microparticles are stored at negative pressurefor up to 1 week, 2 weeks, 3 weeks, 4 weeks, 1 month, 2 months, 3months, 4 months, or more following the manufacture and isolationprocess. In one embodiment, the microparticles are stored for up to 1week to up to 4 weeks at a negative pressure that is less than 700, 550,500, 450, 400, 350, 300, 250, 200, 150, 100, 80, 60, 50, 40, 35, 32, or30 Torr. In one embodiment, the microparticles are stored for up to 1month to up to 2 months at a negative pressure that is less than 700,550, 500, 450, 400, 350, 300, 250, 200, 150, 100, 80, 60, 50, 40, 35,32, or 30 Torr. In one embodiment, the microparticles are stored for upto 3 months at a negative pressure that is less than 700, 550, 500, 450,400, 350, 300, 250, 200, 150, 100, 80, 60, 50, 40, 35, 32, or 30 Torr.

III. Mildly Surface Treated Aggregating Microparticles and Methods

In one aspect, the improved microparticles and microparticle suspensionsare made from mildly surface treated solid biodegradable microparticlesthat upon injection in vivo, aggregate to a larger particle (pellet) ina manner that reduces unwanted side effects of the smaller particles andare suitable for long term (for example, up to or at least three month,up to four month, up to five month, up to six months, up to sevenmonths, up to eight months, up to nine months or longer) sustaineddelivery of a therapeutic agent. In one embodiment, the lightly surfacetreated solid biodegradable microparticles are suitable for ocularinjection, at which point the particles aggregate to form a pellet andthus remains outside the visual axis as not to significantly impairvision. The particles can aggregate into one or several pellets. Thesize of the aggregate depends on the mass (weight) of the particlesinjected.

The mildly surface treated biodegradable microparticles provided hereinare distinguished from “scaffold” microparticles, which are used fortissue regrowth via pores that cells or tissue material can occupy. Incontrast, the present microparticles are designed to be solid materialsof sufficiently low porosity so that they can aggregate to form a largercombined particle that erodes primarily by surface erosion for long-termcontrolled drug delivery.

The surface modified solid aggregating microparticles of the presentinvention are suitable, for example, for intravitreal injection,implant, periocular delivery, or delivery in vivo outside the eye.

The surface modified solid aggregating microparticles of the presentinvention are also suitable for systemic, parenteral, transmembrane,transdermal, buccal, subcutaneous, endosinusial, intra-abdominal,intra-articular, intracartilaginous, intracerebral, intracoronal,dental, intradiscal, intramuscular, intratumor, topical, or vaginaldelivery in any manner useful for in vivo delivery.

In one embodiment, the invention is thus surface-modified solidaggregating microparticles that include at least one biodegradablepolymer, wherein the surface-modified solid aggregating microparticleshave a solid core, include a therapeutic agent, have a modified surfacewhich has been treated under mild conditions at a temperature at or lessthan about 18° C. to remove surface surfactant or cause surface polymerto partially degrade, are sufficiently small to be injected in vivo, andaggregate in vivo to form at least one pellet of at least 500 μm in vivoin a manner that provides sustained drug delivery in vivo for at leastone, two, three, four, five, six seven, eight, nine, ten, eleven, twelvemonths or more. The surface modified solid aggregating microparticlesare suitable, for example, for an intravitreal injection, implant,including an ocular implant, periocular delivery or delivery in vivooutside of the eye. In certain embodiments, the therapeutic agent is aprodrug as described herein. In certain embodiments, microparticles havealso been treated for enhanced wettability.

Alternatively, the surface treatment is conducted at a temperature at orless than about 10° C., 8° C. or 5° C.

The surface treatment can be carried out at any pH that achieves thedesired purpose. Nonlimiting examples of the pH are between about 6 andabout 8, 6.5 and about 7.5, about 1 and about 4; about 4 and about 6;and 6 and about 8. In one embodiment, the surface treatment can beconducted at a pH between about 8 and about 10. In one embodiment, thesurface treatment can be conducted at a pH between about 10.0 and about13.0. In one embodiment, the surface treatment can be conducted at a pHbetween about 10.0 and about 12.0. In one embodiment, the surfacetreatment can be conducted at a pH between about 12 and about 14. In oneembodiment, the surface treatment can be conducted with an organicsolvent. In one embodiment, the surface treatment can be conducted withethanol. In other various embodiments, the surface treatment is carriedout in a solvent selected from methanol, ethyl acetate and ethanol.Nonlimiting examples are ethanol with an aqueous organic base; ethanoland aqueous inorganic base; ethanol and sodium hydroxide; ethanol andpotassium hydroxide; an aqueous acidic solution in ethanol; aqueoushydrochloric acid in ethanol; and aqueous potassium chloride in ethanol.

Examples of solid cores included in the present invention include solidcores comprising a biodegradable polymer with less than 10 percentporosity, 8 percent porosity, 7 percent porosity, 6 percent porosity, 5percent porosity, 4 percent porosity, 3 percent porosity, or 2 percentporosity. Porosity as used herein is defined by ratio of void space tototal volume of the surface-modified solid aggregating microparticle.

The surface-modified solid aggregating microparticles of the presentinvention provides sustained delivery for at least one month, or atleast two months, or at least three months, or at least four months, orat least five months, or at least six months, or at least seven months,or at least eight months, or at least nine months, or at least tenmonths, or at least eleven months, or at least twelve months.

The therapeutic agent delivered by the surface-modified solidaggregating microparticle is in one embodiment a pharmaceutical drug ora biologic. In nonlimiting examples, the pharmaceutical drugs includesunitinib, another tyrosine kinase inhibitor, an anti-inflammatory drug,an antibiotic, an immunosuppressing agent, an anti-VEGF agent, ananti-PDGF agent, or other therapeutic agents as described below. In oneembodiment, the tyrosine kinase inhibitor is selected from Tivosinib,Imatinib, Gefitinib, Erlotinib, Lapatinib, Canertinib, Semaxinib,Vatalaninib, Sorafenib, Axitinib, Pazopanib, Dasatinib, Nilotinib,Crizotinib, Ruxolitinib, Vandetanib, Vemurafenib, Bosutinib,Cabozantinib, Regorafenib, Vismodegib, and Ponatinib.

In one embodiment the surface-modified solid aggregating microparticlehas a mean diameter between 10 and 60 μm, 20 and 50 μm, 20 and 40 μm, 20and 30 μm, 25 and 40 μm, or 25 and 35 μm.

Further, the surface-modified solid aggregating microparticles of thedisclosed invention can aggregate to produce at least one pellet whenadministered in vivo that has a diameter of at least about 300 μm, 400μm, 500 μm, 600 μm, 700 μm, 1 mm, 1.5 mm, 2 mm, 3 mm, 4 mm, or 5 mm.

In one embodiment, the surface-modified solid aggregating microparticlesof the present invention produces a pellet in vivo that releases thetherapeutic agent without a burst of more than about 10 percent or 15percent of the total payload of the therapeutic agent over a one week,or a five, four, three, two day or one day period.

In some embodiments, the long-term controlled drug delivery isaccomplished by a combination of surface erosion of an aggregatedmicroparticle over several months (for example, one, two, three, or fourmonths or more) followed by erosion of remaining parts of the aggregatedmicroparticle, followed by slow release of active material from in vivoproteins to which it has bound over the period of long term release fromthe aggregated particle. In another embodiment, the microparticledegrades substantially by surface erosion over a period of at leastabout one, two, three, four, five or six months or more.

In another embodiment, the surface-modified solid aggregatingmicroparticles of the present invention have a drug loading of 1-40percent, 5-25 percent, or 5-15 percent weight/weight.

Examples of polymeric compositions included in surface-modified solidaggregating microparticles of the present invention include, but are notlimited to: poly(lactide co-glycolide); poly(lactide-co-glycolide)covalently linked to polyethylene glycol; more than one biodegradablepolymer or copolymer mixed together, for example, a mixture ofpoly(lactide-co-glycolide) and poly(lactide-co-glycolide) covalentlylinked to polyethylene glycol, a mixture of poly(lactic acid) andpoly(lactide-co-glycolide) covalently linked to polyethylene glycol, ora mixture of poly(lactic acid), poly(lactide-co-glycolide) andpoly(lactide-co-glycolide) covalently linked to polyethylene glycol;poly(lactic acid); a surfactant, such as polyvinyl alcohol (which can behydrolyzed polyvinyl acetate).

In another embodiment, the invention is an injectable material thatincludes the microparticles of the present invention in apharmaceutically acceptable carrier for administration in vivo. Theinjectable material may include a compound that inhibits aggregation ofmicroparticles prior to injection and/or a viscosity enhancer and/or asalt. In one embodiment, the injectable material has a range ofconcentration of the surface-modified solid aggregating microparticlesof about 50-700 mg/ml, 500 or less mg/ml, 400 or less mg/ml, 300 or lessmg/ml, 200 or less mg/ml, or 150 or less mg/ml.

The present invention further includes a process for the preparation ofsurface-modified solid aggregating microparticles that includes

-   -   (i) a first step of preparing microparticles comprising one or        more biodegradable polymers by dissolving or dispersing the        polymer(s) and a therapeutic agent in one or more solvents to        form a polymer and therapeutic agent solution or dispersion,        mixing the polymer and the therapeutic agent solution or        dispersion with an aqueous phase containing a surfactant to        produce microparticles that contain the therapeutic agent,        polymer and surfactant; and    -   (ii) a second step of mildly surface-only treating the        microparticles of step (i) at a temperature at or below about        18° C. for optionally up to about 140, 120, 110, 100, 90, 80,        70, 60, 50, 40, 30, 10, 8, 5, 4, 3, 2, or 1 minutes with an        agent that removes surface surfactant, surface polymers, or        surface oligomers in a manner that does not significantly        produce internal pores; and    -   (iii) isolating the surface treated microparticles.

In one embodiment, the process for the preparation of surface-treatedsolid aggregating microparticles includes a fourth step for improvingthe aggregation potential of the particles by subjecting the particlesto at least one process selected from 1) vacuum treatment, wherein themicroparticles are suspended in a diluent and the suspension is placedunder vacuum prior to use; 2) excipient addition, wherein an excipientis added prior to lyophilization; and 3) sonication, wherein themicroparticles are suspended in a diluent and sonicated; 4) sealing thevial containing the dry powder of particles under vacuum, including butnot limited to high vacuum; or 5) pre-wetting (i.e., resuspending) thesurface-treated microparticles in a diluent for 2-24 hours beforeinjecting into the eye, for example in a hyaluronic acid solution orother sterile solution suitable for ocular injection.

In certain embodiments step (ii) above is carried out at a temperaturebelow 17° C., 15° C., 10° C., or 5° C. Further, step (iii) is optionallycarried out at a temperature below 25° C., below 17° C., 15° C., 10° C.,8° C. or 5° C. Step (ii), for example, can be carried out for less than8, less than 6, less than 4, less than 3, less than 2, or less than 1minutes. In one embodiment, step (ii) is carried out for less than 60,50, 40, 30, 20, or 10 minutes.

In one embodiment, the process of manufacturing surface-modified solidaggregating microparticles includes using an agent that removes surfacesurfactant. Nonlimiting examples include for example, those selectedfrom: aqueous acid, phosphate buffered saline, water, aqueous NaOH,aqueous hydrochloric acid, aqueous potassium chloride, alcohol orethanol.

In one embodiment, the process of manufacturing surface-modified solidaggregating microparticles includes using an agent that removes surfacesurfactant which comprises, for example, a solvent selected from analcohol, for example, ethanol; ether, acetone, acetonitrile, DMSO, DMF,THF, dimethylacetamide, carbon disulfide, chloroform,1,1-dichloroethane, dichloromethane, ethyl acetate, heptane, hexane,methanol, methyl acetate, methyl t-butyl ether (MTBE), pentane,propanol, 2-propanol, toluene, N-methyl pyrrolidinone (NMP), acetamide,piperazine, triethylenediamine, diols, and CO_(2.).

The agent that removes the surface surfactant can comprise a basicbuffer solution. Further, the agent that removes surface surfactant cancomprise a base selected from sodium hydroxide, lithium hydroxide,potassium hydroxide, calcium hydroxide, magnesium hydroxide, lithiumamide, sodium amide, barium carbonate, barium hydroxide, bariumhydroxide hydrate, calcium carbonate, cesium carbonate, cesiumhydroxide, lithium carbonate, magnesium carbonate, potassium carbonate,sodium carbonate, strontium carbonate, ammonia, methylamine, ethylamine,propylamine, isopropylamine, dimethylamine, diethylamine, dipropylamine,diisopropylamine, trimethylamine, triethylamine, tripropylamine,triisopropylamine, aniline, methylaniline, dimethylaniline, pyridine,azajulolidine, benzylamine, methylbenzylamine, dimethylbenzylamine,DABCO, 1,5-diazabicyclo[4.3.0]non-5-ene,1,8-diazabicyclo[5.4.0]non-7-ene, 2,6-lutidine, morpholine, piperidine,piperazine, Proton-sponge, 1,5,7-Triazabicyclo[4.4.0]dec-5-ene,tripelennamine, ammonium hydroxide, triethanolamine, ethanolamine, andTrizma.

In one embodiment, the process of manufacturing surface-modified solidaggregating microparticles includes using an agent that removes surfacesurfactant, for example, those selected from the following: aqueousacid, phosphate buffered saline, water, or NaOH in the presence of asolvent such as an alcohol, for example, ethanol, ether, acetone,acetonitrile, DMSO, DMF, THF, dimethylacetamide, carbon disulfide,chloroform, 1,1-dichloroethane, dichloromethane, ethyl acetate, heptane,hexane, methanol, methyl acetate, methyl t-butyl ether (MTBE), pentane,ethanol, propanol, 2-propanol, toluene, N-methyl pyrrolidinone (NMP),acetamide, piperazine, triethylenediamine, diols, and CO_(2.).

In one embodiment, the agent that removes the surface surfactant cancomprise an aqueous acid. The agent that removes the surface surfactantcan comprise an acid derived from inorganic acids including, but notlimited to, hydrochloric, hydrobromic, sulfuric, sulfamic, phosphoric,nitric and the like; or organic acids including, but not limited to,acetic, propionic, succinic, glycolic, stearic, lactic, malic, tartaric,citric, ascorbic, pamoic, maleic, hydroxymaleic, phenylacetic, glutamic,benzoic, salicylic, mesylic, esylic, besylic, sulfanilic,2-acetoxybenzoic, fumaric, toluenesulfonic, methanesulfonic, ethanedisulfonic, oxalic, isethionic, HOOC—(CH₂)_(n)—COOH where n is 0-4, andthe like.

In one embodiment, the agent that removes surface surfactant is not adegrading agent of the biodegradable polymer under the conditions of thereaction. The hydrophilicity of the microparticles can be decreased byremoving surfactant.

In one embodiment, the process of manufacturing surface-modified solidaggregating microparticles comprises using an agent that removes surfacesurfactant that comprises a solvent selected from an alcohol, forexample, ethanol, ether, acetone, acetonitrile, DMSO, DMF, THF,dimethylacetamide, carbon disulfide, chloroform, 1,1-dichloroethane,dichloromethane, ethyl acetate, heptane, hexane, methanol, methylacetate, methyl t-butyl ether (MTBE), pentane, ethanol, propanol,2-propanol, toluene, N-methyl pyrrolidinone (NMP), acetamide,piperazine, triethylenediamine, diols, and CO_(2.). In a typicalembodiment the process of surface treating, comprises an agent thatremoves surface surfactant that comprises ethanol.

The encapsulation efficiency of the process of manufacturingsurface-modified solid aggregating microparticles depends on themicroparticle forming conditions and the properties of the therapeuticagent. In certain embodiments, the encapsulation efficiency can begreater than about 50 percent, greater than about 75 percent, greaterthan about 80 percent, or greater than about 90 percent.

In one embodiment, the process of manufacturing surface-modified solidaggregating microparticles includes 5/95, 10/90, 15/85, 20/80, 25/75,30/70, 35/65, 40/60, 45/55, 50/50, 55/45, 60/40, 65/35, 70/30, 75/25,80/20, 85/15, 90/10, 95/5 PLGA as a biodegradable polymer. In oneembodiment, the process of manufacturing surface-modified solidaggregating microparticles includes 50/50 PLGA as a biodegradablepolymer.

In one embodiment, the process of manufacturing surface-modified solidaggregating microparticles includes PLA as a biodegradable polymer. Inone embodiment, the process of manufacturing surface-modified solidaggregating microparticles includes PLA and PLGA as a biodegradablepolymer. In one embodiment, the process of manufacturingsurface-modified solid aggregating microparticles includes PLA and 75/25PLGA as a biodegradable polymer. In one embodiment, the process ofmanufacturing surface-modified solid aggregating microparticles includesPLA and 50/50 PLGA as a biodegradable polymer. In one embodiment, theprocess of manufacturing surface-modified solid aggregatingmicroparticles includes PLGA as a biodegradable polymer.

In one embodiment, the process of manufacturing surface-modified solidaggregating microparticles is carried out below about a pH of 14 andabove a pH of 12, below a pH of 12 and above a pH of 10, below a pH ofabout 10 and above a pH of 8, below about a pH of 8 and above a pH ofabout 6, neutral pH, below about a pH of 7 and above a pH of 4, belowabout a pH of 4 and above a pH of about 1.0.

In one embodiment, step (ii) above is carried out for a time of aboutless than 140, 120, 110, 100, 90, 60, 40, 30, 20, 10, 3, 2, or 1minutes.

In yet another embodiment, a method for the treatment of an oculardisorder is provided that includes administering to a host in needthereof surface-modified solid aggregating microparticles that includean effective amount of a therapeutic agent, wherein the therapeuticagent containing surface-modified solid aggregating microparticles areinjected into the eye and in vivo aggregate to form at least one pelletof at least 500 μm that provides sustained drug delivery for at leastone, two, or three, four, five, six, seven, eight, nine, ten, eleven,twelve or more months in such a manner that the pellet stayssubstantially outside the visual axis as not to significantly impairvision. In one embodiment, the therapeutic agent is a prodrug asdescribed herein.

In an alternative embodiment, the weight percent of surface-modifiedsolid aggregating microparticles that are not aggregated into a largerpellet in vivo is about 10 percent or less, 7 percent or less, 5 percentor less, or 2 percent or less by total weight administered.

In one embodiment, the surface-modified solid aggregating microparticlesdo not cause substantial inflammation in the eye.

In another embodiment, the surface-modified solid aggregatingmicroparticles do not cause an immune response in the eye.

In one embodiment, the surface-modified microparticles of the presentinvention, as described herein, are used to treat a medical disorderwhich is glaucoma, a disorder mediated by carbonic anhydrase, a disorderor abnormality related to an increase in intraocular pressure (IOP), adisorder mediated by nitric oxide synthase (NOS), or a disorderrequiring neuroprotection such as to regenerate/repair optic nerves. Inanother embodiment more generally, the disorder treated is allergicconjunctivitis, anterior uveitis, cataracts, dry or wet age-relatedmacular degeneration (AMD), or diabetic retinopathy.

Another embodiment is provided that includes the administration of asurface treated microparticle comprising an effective amount of apharmaceutically active compound or a pharmaceutically acceptable saltthereof, optionally in a pharmaceutically acceptable carrier, to a hostto treat an ocular or other disorder that can benefit from topical orlocal delivery. The therapy can be delivered to the anterior orposterior chamber of the eye. In specific aspects, a surface treatedmicroparticle comprising an effective amount of a pharmaceuticallyactive compound is administered to treat a disorder of the cornea,conjunctiva, aqueous humor, iris, ciliary body, lens sclera, choroid,retinal pigment epithelium, neural retina, optic nerve, or vitreoushumor.

Any of the compositions described can be administered to the eye asdescribed further herein in any desired form of administration,including via intravitreal, intrastromal, intracameral, subtenon,sub-retinal, retrobulbar, peribulbar, suprachoroidal, subchoroidal,conjunctival, subconjunctival, episcleral, posterior juxtascleral,circumcorneal, tear duct injections, or through a mucus, mucin, or amucosal barrier, in an immediate or controlled release fashion.

In one embodiment, the disclosure provides a beta-adrenergic antagonistfor ocular therapy, which can be released from a surface treatedmicroparticle while maintaining efficacy over an extended time such asup to at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.

In one embodiment, the disclosure provides a prostaglandin or a prodrugthereof for ocular therapy, which can be released from a surface treatedmicroparticle while maintaining efficacy over an extended time such asup to at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.

In one embodiment, the disclosure provides an adrenergic agonist forocular therapy, which can be released from a surface treatedmicroparticle while maintaining efficacy over an extended time such asup to at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.

In one embodiment, the disclosure provides a carbonic anhydraseinhibitor for ocular therapy, which can be released from a surfacetreated microparticle while maintaining efficacy over an extended timesuch as up to at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.

In one embodiment, the disclosure provides a parasympathomimetic agentfor ocular therapy, which can be released from a surface treatedmicroparticle while maintaining efficacy over an extended time such asup to at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.

In one embodiment, the disclosure provides a dual anti-VEGF/anti-PDGFagent for ocular therapy, which can be released from a surface treatedmicroparticle while maintaining efficacy over an extended time such asup to at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.

In one embodiment, the disclosure provides a loop diuretic for oculartherapy, which can be released from a surface treated microparticlewhile maintaining efficacy over an extended time such as up to at least1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.

In one embodiment, the disclosure provides a Rho kinase (ROCK) inhibitorfor ocular therapy, which can be released from a surface treatedmicroparticle while maintaining efficacy over an extended time such asup to at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.

In one embodiment, the disclosure provides a prodrug as described hereinfor ocular therapy, which can be released from a surface treatedmicroparticle while maintaining efficacy over an extended time such asup to at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months.

Methods of treating or preventing ocular disorders, including glaucoma,a disorder mediated by carbonic anhydrase, a disorder or abnormalityrelated to an increase in intraocular pressure (IOP), a disordermediated by nitric oxide synthase (NOS), a disorder requiringneuroprotection such as to regenerate/repair optic nerves, allergicconjunctivitis, anterior uveitis, cataracts, dry or wet age-relatedmacular degeneration (AMD) or diabetic retinopathy are disclosedcomprising administering a therapeutically effective amount of a surfacetreated microparticle comprising a pharmaceutically active compound to ahost, including a human, in need of such treatment. In one embodiment,the host is a human.

In another embodiment, an effective amount of a surface treatedmicroparticle comprising a pharmaceutically active compound is providedto decrease intraocular pressure (IOP) caused by glaucoma. In analternative embodiment, the surface treated microparticle comprising apharmaceutically active compound can be used to decrease intraocularpressure (IOP), regardless of whether it is associated with glaucoma.

In one embodiment, the disorder is associated with an increase inintraocular pressure (IOP) caused by potential or previously poorpatient compliance to glaucoma treatment. In yet another embodiment, thedisorder is associated with potential or poor neuroprotection throughneuronal nitric oxide synthase (NOS). The surface treated microparticlecomprising a pharmaceutically active compound provided herein may thusdampen or inhibit glaucoma in a host, by administration of an effectiveamount in a suitable manner to a host, typically a human, in needthereof.

Methods for the treatment of a disorder associated with glaucoma,increased intraocular pressure (IOP), optic nerve damage caused byeither high intraocular pressure (IOP) or neuronal nitric oxide synthase(NOS) are provided that includes the administration of an effectiveamount of a surface treated microparticle comprising a pharmaceuticallyactive compound are also disclosed.

In one aspect of the present invention, an effective amount of apharmaceutically active compound as described herein is incorporatedinto a surface treated microparticle, e.g., for convenience of deliveryand/or sustained release delivery. The use of materials in micrometerscale provides one the ability to modify fundamental physical propertiessuch as solubility, diffusivity, and drug release characteristics. Thesemicrometer scale agents may provide more effective and/or moreconvenient routes of administration, lower therapeutic toxicity, extendthe product life cycle, and ultimately reduce healthcare costs. Astherapeutic delivery systems, surface treated microparticles can allowtargeted delivery and sustained release.

In another aspect of the present invention, the surface treatedmicroparticle is coated with a surface agent. The present inventionfurther comprises a method of producing surface treated microparticlescomprising a pharmaceutically active compound. The present inventionfurther comprises methods of using the surface treated microparticlescomprising a pharmaceutically active compound to treat a patient.

In one embodiment, surface treated microparticles including apharmaceutically active compound are obtained by forming an emulsion andusing a bead column as described in, for example, U.S. Pat. No.8,916,196.

In one embodiment, surface treated microparticles including apharmaceutically active compound are obtained by using a vibrating meshor microsieve.

In one embodiment, surface treated microparticles including apharmaceutically active compound are obtained by using slurry sieving.

The processes of producing microspheres described herein are amenable tomethods of manufacture that narrow the size distribution of theresultant particles. In one embodiment, the particles are manufacturedby a method of spraying the material through a nozzle with acousticexcitation (vibrations) to produce uniform droplets. A carrier streamcan also be utilized through the nozzle to allow further control ofdroplet size. Such methods are described in detail in: Berkland, C., K.Kim, et al. (2001). “Fabrication of PLG microspheres with preciselycontrolled and monodisperse size distributions.” J Control Release73(1): 59-74; Berkland, C., M. King, et al. (2002). “Precise control ofPLG microsphere size provides enhanced control of drug release rate.” JControl Release 82(1): 137-147; Berkland, C., E. Pollauf, et al. (2004).“Uniform double-walled polymer microspheres of controllable shellthickness.” J Control Release 96(1): 101-111.

In another embodiment, microparticles of uniform size can bemanufactured by methods that utilize microsieves of the desired size.The microsieves can either be used directly during production toinfluence the size of microparticles formed, or alternatively postproduction to purify the microparticles to a uniform size. Themicrosieves can either be mechanical (inorganic material) or biologicalin nature (organic material such as a membrane). One such method isdescribed in detail in U.S. Pat. No. 8,100,348.

In one embodiment, the surface treated microparticles comprise atherapeutically active compound and have a particle size of 25<Dv50<40μm, Dv90<45 μm.

In one embodiment, the surface treated microparticles comprise atherapeutically active compound and have a particle size of Dv10>10 μm.

In one embodiment, the surface treated microparticles comprise atherapeutically active compound and have only residual solvents that arepharmaceutically acceptable.

In one embodiment, the surface treated microparticles comprise atherapeutically active compound and afford a total release of greaterthan eighty percent by day 14.

In one embodiment, the surface treated microparticles comprise atherapeutically active agent and have syringeability with aregular-walled 26-, 27-, 28-, 29- or 30-gauge needle of 200 mg/ml withno clogging of the syringe.

In one embodiment, the surface treated microparticles comprise atherapeutically active agent and have syringeability with a thin-walled26-, 27-, 28-, 29- or 30-gauge needle of 200 mg/ml with no clogging ofthe syringe.

In one embodiment, the surface treated microparticles comprisessunitinib have a particle size of 25<Dv50<40 μm, Dv90<45 μm.

In one embodiment, the surface treated microparticles comprisingsunitinib have a particle size of Dv10>10 μm.

In one embodiment, the surface treated microparticles comprisingsunitinib have only residual solvents that are pharmaceuticallyacceptable.

In one embodiment, the surface treated microparticles comprisingsunitinib afford a total release of greater than eighty percent by day14.

In one embodiment, the surface treated microparticles comprisingsunitinib have syringeability with a regular-walled 26-, 27-, 28-, 29-or 30-gauge needle of 200 mg/ml with no clogging of the syringe.

In one embodiment, the surface treated microparticles comprisingsunitinib have syringeability with a thin-walled 26-, 27-, 28-, 29- or30-gauge needle of 200 mg/ml with no clogging of the syringe.

In one embodiment, the surface treated microparticles comprisingsunitinib have an endotoxin level of less than 0.02 EU/mg.

In one embodiment, the surface treated microparticles comprisingsunitinib have a bioburden level of less than 10 CFU/g.

Biodegradable Polymers

The surface treated microparticles can include one or more biodegradablepolymers or copolymers. The polymers should be biocompatible in thatthey can be administered to a patient without an unacceptable adverseeffect. Biodegradable polymers are well known to those in the art andare the subject of extensive literature and patents. The biodegradablepolymer or combination of polymers can be selected to provide the targetcharacteristics of the microparticles, including the appropriate mix ofhydrophobic and hydrophilic qualities, half-life and degradationkinetics in vivo, compatibility with the therapeutic agent to bedelivered, appropriate behavior at the site of injection, etc.

For example, it should be understood by one skilled in the art that bymanufacturing a microparticle from multiple polymers with varied ratiosof hydrophobic, hydrophilic, and biodegradable characteristics that theproperties of the microparticle can be designed for the target use. Asan illustration, a microparticle manufactured with 90 percent PLGA and10 percent PEG is more hydrophilic than a microparticle manufacturedwith 95 percent PLGA and 5 percent PEG. Further, a microparticlemanufactured with a higher content of a less biodegradable polymer willin general degrade more slowly. This flexibility allows microparticlesof the present invention to be tailored to the desired level ofsolubility, rate of release of pharmaceutical agent, and rate ofdegradation.

In certain embodiments, the microparticle includes apoly(α-hydroxyacid). Examples of poly(α-hydroxyacids) include polylactic acid (PLA), polyglycolic acid (PGA),poly(D,L-lactide-co-glycolide)(PLGA), and poly D,L-lactic acid (PDLLA).polyesters, poly (ε-caprolactone), poly (3-hydroxy-butyrate), poly(s-caproic acid), poly (p-dioxanone), poly (propylene fumarate), poly(ortho esters), polyol/diketene acetals, polyanhydrides, poly (sebacicanhydride) (PSA), poly (carboxybis-carboxyphenoxyphosphazene) (PCPP),poly [bis (p-carboxyphenoxy) methane] (PCPM), copolymers of SA, CPP andCPM (as described in Tamat and Langer in Journal of Biomaterials SciencePolymer Edition, 3, 315-353, 1992 and by Domb in Chapter 8 of TheHandbook of Biodegradable Polymers, Editors Domb A J and Wiseman R M,Harwood Academic Publishers), and poly (amino acids).

In one embodiment, the microparticle includes about at least 90 percenthydrophobic polymer and about not more than 10 percent hydrophilicpolymer. Examples of hydrophobic polymers include polyesters such aspoly lactic acid (PLA), polyglycolic acid (PGA),poly(D,L-lactide-co-glycolide)(PLGA), and poly D,L-lactic acid (PDLLA);polycaprolactone; polyanhydrides, such as polysebacic anhydride,poly(maleic anhydride); and copolymers thereof. Examples of hydrophilicpolymers include poly(alkylene glycols) such as polyethylene glycol(PEG), polyethylene oxide (PEO), and poly(ethylene glycol) amine;polysaccharides; poly(vinyl alcohol) (PVA); polypyrrolidone;polyacrylamide (PAM); polyethylenimine (PEI); poly(acrylic acid);poly(vinylpyrolidone) (PVP); or a copolymer thereof.

In one embodiment, the microparticle includes about at least 85 percenthydrophobic polymer and at most 15 percent hydrophilic polymer.

In one embodiment, the microparticle includes about at least 80 percenthydrophobic polymer and at most 20 percent hydrophilic polymer.

In one embodiment, the microparticle includes PLA. In one embodiment,the PLA is acid-capped.

In one embodiment, the PLA is ester-capped.

In one embodiment, the microparticle includes PLA and PLGA-PEG.

In one embodiment, the microparticle includes PLA and PLGA-PEG and PVA.

In one embodiment, the microparticle includes PLA, PLGA, and PLGA-PEG.

In one embodiment, the microparticle includes PLA, PLGA, and PLGA-PEGand PVA.

In one embodiment, the microparticle includes PLGA.

In one embodiment, the microparticle includes a copolymer of PLGA andPEG.

In one embodiment, the microparticle includes a copolymer of PLA andPEG.

In one embodiment, the microparticle comprises PLGA and PLGA-PEG, andcombinations thereof.

In one embodiment, the microparticle comprises PLA and PLA-PEG.

In one embodiment, the microparticle includes PVA.

In one embodiment, the microparticles include PLGA, PLGA-PEG, PVA, orcombinations thereof.

In one embodiment, the microparticles include the biocompatible polymersPLA, PLA-PEG, PVA, or combinations thereof.

In one embodiment, the microparticles have a mean size of about 20 μm toabout 50 μm, 25 μm to about 45 μm, 25 μm to about 30 μm and a mediansize of about 29 μm to about 31 μm before surface treatment.

In one embodiment, the microparticles after surface treatment have aboutthe same mean size and median size. In another embodiment, themicroparticles after surface treatment have a mean size which is largerthan the median size. In another embodiment, the microparticles aftersurface treatment have a mean size which is smaller than the mediansize.

In one embodiment, the microparticles have a mean size of about 20 μm toabout 50 μm, 25 μm to about 45 μm, 25 μm to about 30 μm, or 30 to 33 μmand a median size of about 31 μm to about 33 μm after surface treatmentwith approximately 0.0075 M NaOH/ethanol to 0.75 M NaOH/ethanol (30:70,v:v).

In one embodiment, the microparticles have a mean size of about 20 μm toabout 50 μm, 25 μm to about 45 μm, 25 μm to about 30 μm or 30 to 33 μmand a median size of about 31 μm to about 33 μm after surface treatmentwith approximately 0.75 M NaOH/ethanol to 2.5 M NaOH/ethanol (30:70,v:v).

In one embodiment, the microparticles have a mean size of about 20 μm toabout 50 μm, about 25 μm to about 45 μm, about 25 μm to about 30 μm or30 to 33 μm and a median size of about 31 μm to about 33 μm aftersurface treatment with approximately 0.0075 M HCl/ethanol to 0.75 MNaOH/ethanol (30:70, v:v).

In one embodiment, the microparticles have a mean size of about 20 μm toabout 50 μm, about 25 μm to about 45 μm, about 25 μm to about 30 μm or30 to 33 μm and a median size of about 31 μm to about 33 μm aftersurface treatment with approximately 0.75 M NaOH/ethanol to 2.5 MHCl/ethanol (30:70, v:v).

In one embodiment, a surface-modified solid aggregating microparticle ismanufactured using a wet microparticle.

In one embodiment, the surface-modified solid aggregating microparticlecan release a therapeutic agent over a longer period of time whencompared to a non-surface treated microparticle.

In one embodiment, a surface-modified solid aggregating microparticlecontains less surfactant than a microparticle prior to the surfacemodification.

In one embodiment, a surface-modified solid aggregating microparticle ismore hydrophobic than a microparticle prior to the surface modification.

In one embodiment, a surface-modified solid aggregating microparticle isless inflammatory than a non-surface treated microparticle.

In one embodiment, the agent that removes the surface surfactant of asurface-modified solid aggregating microparticle comprises a solventthat partially dissolves or swells the surface-modified solidaggregating microparticle.

In one aspect of the present invention, an effective amount of apharmaceutically active compound as described herein is incorporatedinto a surface treated microparticle, e.g., for convenience of deliveryand/or sustained release delivery. The use of materials provides theability to modify fundamental physical properties such as solubility,diffusivity, and drug release characteristics. These micrometer scaleagents may provide more effective and/or more convenient routes ofadministration, lower therapeutic toxicity, extend the product lifecycle, and ultimately reduce healthcare costs. As therapeutic deliverysystems, surface treated microparticles can allow targeted delivery andsustained release.

Surfactants

In one embodiment, the manufacture of the microparticle includes asurfactant. Examples of surfactants include, for example,polyoxyethylene glycol, polyoxypropylene glycol, decyl glucoside, laurylglucoside, octyl glucoside, polyoxyethylene glycol octylphenol, TritonX-100, glycerol alkyl ester, glyceryl laurate, cocamide MEA, cocamideDEA, dodecyldimethylamine oxide, and poloxamers. Examples of poloxamersinclude, poloxamers 188, 237, 338 and 407. These poloxamers areavailable under the trade name Pluronic® (available from BASF, MountOlive, N.J.) and correspond to Pluronic® F-68, F-87, F-108 and F-127,respectively. Poloxamer 188 (corresponding to Pluronic® F-68) is a blockcopolymer with an average molecular mass of about 7,000 to about 10,000Da, or about 8,000 to about 9,000 Da, or about 8,400 Da. Poloxamer 237(corresponding to Pluronic® F-87) is a block copolymer with an averagemolecular mass of about 6,000 to about 9,000 Da, or about 6,500 to about8,000 Da, or about 7,700 Da. Poloxamer 338 (corresponding to Pluronic®F-108) is a block copolymer with an average molecular mass of about12,000 to about 18,000 Da, or about 13,000 to about 15,000 Da, or about14,600 Da. Poloxamer 407 (corresponding to Pluronic® F-127) is apolyoxyethylene-polyoxypropylene triblock copolymer in a ratio ofbetween about E101 P56 E101 to about E106 P70 E106, or about E101P56E101, or about E106 P70 E106, with an average molecular mass of about10,000 to about 15,000 Da, or about 12,000 to about 14,000 Da, or about12,000 to about 13,000 Da, or about 12,600 Da.

Additional examples of surfactants that can be used in the inventioninclude, but are not limited to, polyvinyl alcohol (which can behydrolyzed polyvinyl acetate), polyvinyl acetate, Vitamin E-TPGS,poloxamers, cholic acid sodium salt, dioctyl sulfosuccinate sodium,hexadecyltrimethyl ammonium bromide, saponin, TWEEN® 20, TWEEN® 80,sugar esters, Triton X series, L-a-phosphatidylcholine (PC),1,2-dipalmitoylphosphatidycholine (DPPC), oleic acid, sorbitantrioleate, sorbitan mono-oleate, sorbitan monolaurate, polyoxyethylene(20) sorbitan monolaurate, polyoxyethylene (20) sorbitan monooleate,natural lecithin, oleyl polyoxyethylene (2) ether, stearylpolyoxyethylene (2) ether, lauryl polyoxyethylene (4) ether, blockcopolymers of oxyethylene and oxypropylene, synthetic lecithin,diethylene glycol dioleate, tetrahydrofurfuryl oleate, ethyl oleate,isopropyl myristate, glyceryl monooleate, glyceryl monostearate,glyceryl monoricinoleate, cetyl alcohol, stearyl alcohol,cetylpyridinium chloride, benzalkonium chloride, olive oil, glycerylmonolaurate, corn oil, cotton seed oil, sunflower seed oil, lecithin,oleic acid, and sorbitan trioleate.

It should be recognized by one skilled in the art that some surfactantscan be used as polymers in the manufacture of the microparticle. Itshould also be recognized by one skilled in the art that in somemanufacture the microparticle may retain a small amount of surfactantwhich allows further modification of properties as desired.

IV. Biodegradable Polymeric-Containing Microparticles

In certain aspects, solid aggregating microparticles are provided thatinclude a poly(α-hydroxyacid) biodegradable polymer, for examplepoly-lactic acid (PLA) biodegradable polymer, and a hydrophobic polymercovalently bound to a hydrophilic polymer, for example PLGA-PEGbiodegradable polymer, wherein the solid aggregating microparticles havea solid core, include a therapeutic agent, are sufficiently small to beinjected in vivo, and are capable of aggregating in vivo. In oneembodiment, the microparticles aggregate in vivo to form at least onepellet of at least 500 μm in vivo to provide sustained drug delivery invivo for at least one month, two months, three months, four months, fivemonths, six months, seven months, eight months, nine months, or more. Inone embodiment, the microparticles are about 10 μm to about 50 μm, fromabout 20 μm to about 45 μm, from about 25 μm to about 35 μm.

It has been discovered that the inclusion of PLA in certainmicroparticle formulations allows for the achievement of long-term slowsubstantially surface erosion for example, 9 months, 10 months, 11months, 12 months or greater. In some embodiments, nearly zero-order orlinear release drug delivery in vivo, can be achieved.

As contemplated herein, PLA for use in the present invention can includeany known variant, for example, but not limited to, PLLA (Poly-L-lacticAcid), racemic PLLA (Poly-L-lactic Acid), PDLA (Poly-D-lactic Acid), andPDLLA (Poly-DL-lactic Acid), or a mixture thereof. In one embodiment,the PLA is Poly-L-lactic Acid. The PLA can be ester end-capped or acidend-capped.

In one embodiment, the PLA comprises at least about 40%, 45%, 50%, 55%,60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, or99.9% of the microparticle. In one embodiment, the PLA has a molecularweight between about 30 and 60 kD, about 35 and 55 kD, or about 40 and50 kD. The microparticle further includes a hydrophobic polymercovalently bound to a hydrophilic biodegradable polymer. Hydrophobicdegradable polymers are known in the art, and include, but are notlimited to, polyglycolic acid (PGA),poly(D,L-lactide-co-glycolide)(PLGA), and poly D,L-lactic acid (PDLLA);polycaprolactone; polyanhydrides, such as polysebacic anhydride,poly(maleic anhydride); and copolymers thereof. Hydrophilic polymers areknown in the art and include, for example poly(alkylene glycols) such aspolyethylene glycol (PEG), polyethylene oxide (PEO), and poly(ethyleneglycol) amine; polysaccharides; poly(vinyl alcohol) (PVA);polypyrrolidone; polyacrylamide (PAM); polyethylenimine (PEI);poly(acrylic acid); poly(vinylpyrolidone) (PVP); or a copolymer thereof.Hydrophobic polymers covalently bound to hydrophilic polymers include,for example, PLGA-PEG, PLA-PEG, PCL-PEG in an amount from about 0.5percent to about 10 percent, about 0.5 percent to about 5 percent, about0.5 percent to about 4 percent, about 0.5 percent to about 3 percent, orabout 0.1 percent to about 1, 2, 5, or 10 percent. In one embodiment,the hydrophobic polymer covalently bound to the hydrophilic polymer isPLGA-PEG.

In one embodiment, the ratio of PLA/hydrophobic polymer covalently boundto a hydrophilic polymer in the microparticle is between about 40/1 toabout 120/1. In one embodiment, the ratio of PLA/hydrophobic polymercovalently bound to hydrophilic polymer in the microparticle is about45/1, 50/1, 55/1, 60/1, 65/1, 70/1, 75/1, 80/1, 85/1, 90/1, 95/1, 96/1,97/1, 98/1, 99/1, 99.5/1, 99.9/1, 100/1, 101/1, 102/1, 103/1, 104/1,105/1, or greater than 105/1. In one embodiment, the hydrophobic polymercovalently bound to a hydrophilic polymer is PLGA-PEG.

In one embodiment, the PLA/hydrophobic polymer covalently bound tohydrophilic polymer microparticle further comprises an additionalhydrophobic biodegradable polymer, for example polyglycolic acid (PGA),poly(D,L-lactide-co-glycolide)(PLGA), and poly D,L-lactic acid (PDLLA);polycaprolactone; polyanhydrides, such as polysebacic anhydride,poly(maleic anhydride); and copolymers thereof. In one embodiment, theadditional hydrophobic biodegradable polymer comprises about 1%, 5%,10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, or 55% of themicroparticle. In one embodiment, the additional hydrophobic polymer isPLGA. In one embodiment, the ratio of lactide/glycolide in the PLGA isabout 5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60, 45/55,50/50, 55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, or 95/5.The PLGA can be acid end-capped or ester end-capped. The PLA can be acidend-capped or ester end-capped.

In one embodiment, the microparticle contains PLA, PLGA, and PLGA-PEG.In one embodiment, the ratio of PLA/PLGA/PLGA-PEG in the microparticleis about 5/95/1, 10/90/1, 15/85/1, 20/80/1, 25/75/1, 30/70/1, 35/65/1,40/60/1, 45/55/1, 40/60/1, 45/55/1, 50/50/1, 55/45/1, 60/40/1, 65/35/1,70/30/1, 75/25/1, 80/20/1, 85/15/1, 90/10/1, 95/5/1, or 100/1/1. In oneembodiment, PLA-PEG or PLC-PEG is substituted for PLGA-PEG.

In one embodiment, the microparticles comprise PLA/PLGA45k-PEG5k. ThePLA can be ester or acid end-capped. In one embodiment, the PLA is acidend-capped. In one embodiment, the microparticles comprisePLA/PLGA45k-PEG5k in a ratio of between about 100/1 to 80/20, about100/1, 95/5, 90/10, 85/15, or 80/20. In one embodiment, themicroparticles comprise PLA/PLGA7525/PLGA45k-PEG5k in a ratio of betweenabout 99/1/1 to 1/99/1, about 99/1/1, 95/5/1, 90/10/1, 85/15/1, 80/20/1,75/25/1, 70/30/1, 65/35/1, 60/40/1, 55/45/1, 50/50/1, 45/55/1, 40/60/1,35/65/1, 30/70/1, 25/75/1, 20/80/1, 15/85/1, 10/90/1, 5/95/1, or 1/99/1.The PLGA7525 and PLA can be acid or ester end capped. In one embodiment,both the PLGA7525 and PLA are acid end-capped. In one embodiment, themicroparticles comprise PLA/PLGA5050/PLGA45k-PEG5k. In one embodiment,the microparticles comprise PLA/PLGA5050/PLGA45k-PEG5k in a ratio ofabout 99/1/1, 95/5/1, 90/10/1, 85/15/1, 80/20/1, 75/25/1, 70/30/1,65/35/1, 60/40/1, 55/45/1, 50/50/1, 45/55/1, 40/60/1, 35/65/1, 30/70/1,25/75/1, 20/80/1, 15/85/1, 10/90/1, 5/95/1, or 1/99/1. The PLA andPLGA5050 can be acid or ester end-capped. In one embodiment, both thePLA and PLGA are acid end-capped.

In one embodiment, the PLA microparticles described herein is surfacemodified. In one embodiment, the microparticles have a modified surfacewhich has been treated under mild conditions at a temperature at or lessthan about 18° C. to remove surface surfactant or cause surface polymerto partially degrade. The solid aggregating microparticles are suitable,for example, for an intravitreal injection, implant, including an ocularimplant, periocular delivery, or delivery in vivo outside of the eye.

In one embodiment, the aggregate formed in vivo is a blend or mix ofmicroparticles, wherein at least one of the microparticles includes apoly-lactic acid (PLA) biodegradable polymer and a hydrophobicbiodegradable polymer covalently linked to a hydrophilic polymer, forexample PLGA-PEG biodegradable polymer. In one embodiment, the mix orblend includes one or more microparticles comprised of a non-PLApolymer. In one embodiment, the mix or blend includes PLA/PLGA-PEGmicroparticles and PLGA/PLGA-PEG microparticles. In one embodiment, themix or blend comprises a ratio of PLA/PLGA-PEG to PLGA/PLGA-PEG of about1/99, 5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60, 45/55,50/50, 55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, 95/5, or99/1. In one embodiment, the ratio of lactide/glycolide in the PLGA orPLGA-PEG is about 5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60,45/55, 50/50, 55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, or95/5. The PLGA can be acid end capped or ester end capped. In oneembodiment, the PLGA is a block co-polymer, for example, diblock,triblock, multiblock, or star-shaped block. In one embodiment, the PLGAis a random co-polymer.

In one embodiment, the mix or blend includes PLA/PLGA-PEG microparticlesand PLA/PLGA/PLGA-PEG microparticles. In one embodiment, the mix orblend comprises a ratio of PLA/PLGA-PEG to PLA/PLGA/PLGA-PEG of about1/99, 5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60, 45/55,50/50, 55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, 95/5, or99/1. In one embodiment, the ratio of lactide/glycolide in the PLGA orPLGA-PEG is about 5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60,45/55, 50/50, 55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, or95/5. In one embodiment, the PLGA is in a lactide/glycolide ratio of95/5, 90/10, 85/15, 80/20, 75/25, 70/30, 65/35, 60/40, 55/45, 50/50,45/55, 40/60, 35/65, 30/70, 25/75, 20/80, 15/85, 10/90, 5/95. The PLGAcan be acid end capped or ester end capped. In one embodiment, the PLGAis a block co-polymer, for example, diblock, triblock, multiblock, orstar-shaped block. In one embodiment, the PLGA is a random co-polymer.

In one embodiment, the blend or mix of microparticles is comprised of aPLA/PLGA-PEG microparticle, wherein the PLA comprises from about 80% to99.9% of the microparticle, and a PLGA/PLGA-PEG microparticle, whereinthe PLGA comprises from about 80% to 99.9% of the microparticle. In oneembodiment, the blend or mix of microparticles is comprised of aPLA/PLGA45k-PEG5k microparticle and a PLGA7525/PLGA45k-PEG5kmicroparticle in a ratio of from about 1/99 to about 99/1, about 1.99,5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60, 45/55, 50/50,55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, 95/5, or 99/1.In one embodiment, the ratio of PLA/PLGA45k-PEG5k microparticle toPLGA7525/PLGA45k-PEG5k microparticles is between about 20/80 to 40/60,about 20/80, 25/75, 30/70, 35/65, or 40/60. The PLA and PLGA can beester or acid end capped. In one embodiment, the blend or mix ofmicroparticles is comprised of a PLA 4A/PLGA45k-PEG5k microparticle anda PLGA7525 4A/PLGA45k-PEG5k microparticle in a ratio of from about 1/99to about 99/1, about 1.99, 5/95, 10/90, 15/85, 20/80, 25/75, 30/70,35/65, 40/60, 45/55, 50/50, 55/45, 60/40, 65/35, 70/30, 75/25, 80/20,85/15, 90/10, 95/5, or 99/1. In one embodiment, the ratio of PLA4A/PLGA45k-PEG5k microparticle to PLGA7525 4A/PLGA45k-PEG5kmicroparticles is between about 20/80 to 40/60, about 20/80, 25/75,30/70, 35/65, or 40/60.

In one embodiment, the blend or mix of microparticles is comprised of aPLA/PLGA45k-PEG5k microparticle and a PLGA5050/PLGA45k-PEG5kmicroparticle in a ratio of from about 1/99 to about 99/1, about 1.99,5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60, 45/55, 50/50,55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, 95/5, or 99/1.In one embodiment, the ratio of PLA/PLGA45k-PEG5k microparticle toPLGA5050/PLGA45k-PEG5k microparticles is between about 20/80 to 40/60,about 20/80, 25/75, 30/70, 35/65, or 40/60. The PLA and PLGA can beester or acid end capped. In one embodiment, the blend or mix ofmicroparticles is comprised of a PLA 4A/PLGA45k-PEG5k microparticle anda PLGA5050 4A/PLGA45k-PEG5k microparticle in a ratio of from about 1/99to about 99/1, about 1.99, 5/95, 10/90, 15/85, 20/80, 25/75, 30/70,35/65, 40/60, 45/55, 50/50, 55/45, 60/40, 65/35, 70/30, 75/25, 80/20,85/15, 90/10, 95/5, or 99/1. In one embodiment, the ratio of PLA4A/PLGA45k-PEG5k microparticle to PLGA5050 4A/PLGA45k-PEG5kmicroparticles is between about 20/80 to 40/60, about 20/80, 25/75,30/70, 35/65, or 40/60.

In one embodiment, the blend or mix of microparticles is comprised of aPLA/PLGA/PLGA-PEG microparticle and a PLGA/PLGA-PEG microparticle, Inone embodiment, the blend or mix of microparticles is comprised of aPLA/PLGA/PLGA45k-PEG5k microparticle and a PLGA/PLGA45k-PEG5kmicroparticle in a ratio of from about 1/99 to about 99/1, about 1.99,5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60, 45/55, 50/50,55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, 95/5, or 99/1.In one embodiment, the blend or mix of microparticles is comprised of aPLA/PLGA7525/PLGA45k-PEG5k microparticle and a PLGA7525/PLGA45k-PEG5kmicroparticle in a ratio of from about 1/99 to about 99/1, about 1.99,5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60, 45/55, 50/50,55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, 95/5, or 99/1.In one embodiment, the blend or mix of microparticles is comprised of aPLA/PLGA7525/PLGA45k-PEG5k microparticle and a PLGA5050/PLGA45k-PEG5kmicroparticle in a ratio of from about 1/99 to about 99/1, about 1.99,5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60, 45/55, 50/50,55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, 95/5, or 99/1.In one embodiment, the blend or mix of microparticles is comprised of aPLA/PLGA5050/PLGA45k-PEG5k microparticle and a PLGA7525/PLGA45k-PEG5kmicroparticle in a ratio of from about 1/99 to about 99/1, about 1.99,5/95, 10/90, 15/85, 20/80, 25/75, 30/70, 35/65, 40/60, 45/55, 50/50,55/45, 60/40, 65/35, 70/30, 75/25, 80/20, 85/15, 90/10, 95/5, or 99/1.The PLA and PLGA can be acid end capped or ester end capped.

In one embodiment, the microparticle comprises a blend or mix of ratioof PLA4A/PLGA45k-PEG5k and PLGA7525 4A/PLGA45k-PEG5k. In one embodiment,the blend or mix of microparticles comprise a ratio of PLA4A/PLGA45k-PEG5k microparticle to PLGA7525 4A/PLGA45k-PEG5kmicroparticles is between about 20/80 to 40/60, about 20/80, 25/75,30/70, 35/65, or 40/60. In one embodiment, the blend or mix ofmicroparticles is comprised of a PLA 4A/PLGA45k-PEG5k microparticle anda PLGA5050 4A/PLGA45k-PEG5k microparticle in a ratio of from about 1/99to about 99/1, about 1.99, 5/95, 10/90, 15/85, 20/80, 25/75, 30/70,35/65, 40/60, 45/55, 50/50, 55/45, 60/40, 65/35, 70/30, 75/25, 80/20,85/15, 90/10, 95/5, or 99/1. In one embodiment, the ratio of PLA4A/PLGA45k-PEG5k microparticle to PLGA5050 4A/PLGA45k-PEG5kmicroparticles is between about 20/80 to 50/50, about 20/80, 25/75,30/70, 35/65, 40/60, or 50/50.

As contemplated herein, PLA, as utilized herein, can be replaced with adifferent poly(α-hydroxyacid) biodegradable polymer, for example,polyglycolic acid (PGA), poly(D,L-lactide-co-glycolide)(PLGA), and polyD,L-lactic acid (PDLLA). polyesters, poly (6-caprolactone), poly(3-hydroxy-butyrate), poly (s-caproic acid), poly (p-dioxanone), poly(propylene fumarate), poly (ortho esters), polyol/diketene acetals,polyanhydrides, poly (sebacic anhydride) (PSA), poly(carboxybis-carboxyphenoxyphosphazene) (PCPP), poly [bis(p-carboxyphenoxy) methane] (PCPM), copolymers of SA, CPP, CPM, andpoly(amino acids).

Non-limiting embodiments of solid aggregating microparticles,injections, and suspensions include:

(I) A solid aggregating microparticle comprising surface surfactant anda prodrug disclosed herein encapsulated in at least one biodegradablepolymer selected from PLA and PLGA and at least one hydrophobic polymercovalently bound to a hydrophillic polymer, wherein the microparticlehas a mean diameter between 10 μm and 60 μm that:

-   -   (i) has a solid core with less than 10% porosity by ratio of        void space to total volume;    -   (ii) has a modified surface which has been treated under mild        conditions at a temperature less than about 18° C. to remove        surface surfactant; and    -   (iii) is capable of aggregating in vivo to form at least one        pellet of at least 500 μm in vivo capable of sustained drug        delivery in vivo for at least three months.

(II) A solid aggregating microparticle comprising surface surfactant anda tyrosine kinase inhibitor selected from Tivosinib, Imatinib,Gefitinib, Erlotinib, Lapatinib, Canertinib, Semaxinib, Vatalaninib,Sorafenib, Axitinib, Pazopanib, Dasatinib, Nilotinib, Crizotinib,Ruxolitinib, Vandetanib, Vemurafenib, Bosutinib, Cabozantinib,Regorafenib, Vismodegib, and Ponatinib encapsulated in at least onebiodegradable polymer selected from PLA and PLGA and at least onehydrophobic polymer covalently bound to a hydrophillic polymer, whereinthe microparticle has a mean diameter between 10 μm and 60 μm that:

-   -   (i) has a solid core with less than 10% porosity by ratio of        void space to total volume;    -   (ii) has a modified surface which has been treated under mild        conditions at a temperature less than about 18° C. to remove        surface surfactant; and    -   (iii) is capable of aggregating in vivo to form at least one        pellet of at least 500 μm in vivo capable of sustained drug        delivery in vivo for at least three months.

(III) A solid aggregating microparticle comprising surface surfactantand a loop diuretic selected from furosemide, bumetanide, piretanide,ethacrynic acid, etozolin, and ozolinone, encapsulated in at least onebiodegradable polymer selected from PLA and PLGA and at least onehydrophobic polymer covalently bound to a hydrophillic polymer, whereinthe microparticle has a mean diameter between 10 μm and 60 μm that:

-   -   (i) has a solid core with less than 10% porosity by ratio of        void space to total volume;    -   (ii) has a modified surface which has been treated under mild        conditions at a temperature less than about 18° C. to remove        surface surfactant; and    -   (iii) is capable of aggregating in vivo to form at least one        pellet of at least 500 μm in vivo capable of sustained drug        delivery in vivo for at least three months.

(IV) An injectable material that comprises the microparticles of (I),(II), or (III) in a pharmaceutically acceptable carrier foradministration in vivo.

(V) A composition comprising a mixture or blend of solid aggregatingmicroparticles wherein the microparticles are capable of aggregating invivo to form at least one pellet of at least 500 μm in vivo capable ofsustained drug delivery in vivo for at least four months wherein thecomposition comprises:

-   -   (i) a first microparticle with a solid core comprising surface        surfactant and a therapeutic agent encapsulated in PLA and        PLGA-PEG; and    -   (ii) a second microparticle with a solid core comprising surface        surfactant and a therapeutic agent encapsulated in PLGA and        PLGA-PEG; and

(VI) A composition comprising a mixture or blend of solid aggregatingmicroparticles wherein the microparticles are capable of aggregating invivo to form at least one pellet of at least 500 μm in vivo capable ofsustained drug delivery in vivo for at least four months wherein thecomposition comprises:

-   -   (i) a first microparticle with a solid core comprising surface        surfactant and a therapeutic agent encapsulated in PLA and        PLGA-PEG; and    -   (ii) a second microparticle with a solid core comprising surface        surfactant and a therapeutic agent encapsulated in PLA/PLGA and        PLGA-PEG.

(VII) A composition comprising a mixture or blend of solid aggregatingmicroparticles wherein the microparticles are capable of aggregating invivo to form at least one pellet of at least 500 μm in vivo capable ofsustained drug delivery in vivo for at least four months wherein thecomposition comprises:

-   -   (i) a first microparticle with a solid core comprising surface        surfactant and a therapeutic agent encapsulated in PLGA and        PLGA-PEG; and    -   (ii) a second microparticle with a solid core comprising surface        surfactant and a therapeutic agent encapsulated in PLA/PLGA and        PLGA-PEG.

(VIII) An injectable material that comprises the composition of (V),(VI), or (VII) in a pharmaceutically acceptable carrier foradministration in vivo.

Particular embodiments include:

The solid aggregating microparticles of (I), (II), or (III), suitablefor a delivery route selected from the group consisting of intravitreal,intrastromal, intracameral, subtenon, sub-retinal, retrobulbar,peribulbar, suprachoroidal, subchoroidal, conjunctival, subconjunctival,episcleral, posterior juxtascleral, circumcorneal, and tear ductinjections.

The solid aggregating microparticles of (I), (II), or (III), wherein theat least one pellet is capable of sustained delivery for at least fourmonths, at least five months, at least six months, at least sevenmonths, at least eight months, at least nine months, or at least tenmonths.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a pH between about 14 and about12.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a pH between about 12 and about10.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a pH between about 10 and about8.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a pH between about 6.5 and about7.5.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a pH between about 1 and about 6.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a temperature of less than about16° C.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a temperature of less than about10° C.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a temperature of less than about8° C.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a temperature of less than about5° C.

The solid aggregating microparticles of (I), (II), or (III), wherein thesurface modification is carried out at a temperature of less than about2° C.

The solid aggregating microparticles of (I), (II), or (III), wherein thehydrophobic polymer covalently bound to a hydrophilic polymer ispoly(D,L-lactide-co-glycolide) covalently bound to polyethylene glycol(PLGA-PEG).

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLA and PLGA-PEG.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLA PLGA-PEG the ratio of PLA to PLGA-PEG isbetween about 99/1.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLGA PLGA-PEG.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLGA and PLGA-PEG the ratio of PLA to PLGA-PEGis between about 99/1.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLA/PLGA PLGA-PEG.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLA/PLGA PLGA-PEG and the ratio ofPLA/PLGA/PLGA-PEG is about 5/95/1, 10/90/1, 15/85/1, 20/80/1, 25/75/1,30/70/1, 35/65/1, 40/60/1, 45/55/1, 50/50/1, 55/45/1, 60/40/1, 65/35/1,70/30/1, 75/25/1, 80/20/1, 85/15/1, 90/10/1, 95/5/1, or 100/1/1.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLA/PLGA PLGA-PEG and the ratio ofPLA/PLGA/PLGA-PEG is about 95/5/1.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLA/PLGA PLGA-PEG and the ratio ofPLA/PLGA/PLGA-PEG is about 90/10/1.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLA/PLGA PLGA-PEG and the ratio ofPLA/PLGA/PLGA-PEG is about 70/30/1.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise (i) PLGA; (ii) PLGA wherein the PLGA in (ii) hasa different ratio of lactide to glycolide than the PLGA in (i); and,PLGA-PEG.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLGA50:50, PLGA75:25, and PLGA-PEG.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLGA50:50, PLGA85:15, and PLGA-PEG.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles comprise PLGA85:15, PLGA75:25, and PLGA-PEG.

The solid aggregating microparticles of (I), (II), or (III), wherein thePLA is ester end-capped.

The solid aggregating microparticles of (I), (II), or (III), wherein thePLA is acid end-capped.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles have a mean diameter between about 20 and 30 μm.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles have a mean diameter between about 20 and 50 μm.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles have a mean diameter between about 25 and 35 μm.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles have a mean diameter between about 20 and 40 μm.

The solid aggregating microparticles of (I), (II), or (III), wherein themicroparticles have a mean diameter between about 25 and 40 μm.

The injectable material of (IV), wherein the injectable materialcomprises a compound that inhibits aggregation of the microparticlesprior to injection.

The injectable material of (IV), wherein the injectable materialcomprises a sugar.

The injectable material of (IV), wherein the injectable materialcomprises mannitol, sucrose, trehalose, glucose, or lactose.

The injectable material of (IV), wherein the injectable materialcomprises a viscosity enhancer.

The injectable material of (IV), wherein the injectable materialcomprises hyaluronic acid.

The injectable material of (IV), wherein the injectable materialcomprises sodium hyaluronate.

The injectable material of (IV), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about100-600 mg/ml.

The injectable material of (IV), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about500 or less mg/ml.

The injectable material of (IV), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about300 or less mg/ml.

The injectable material of (IV), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about200 or less mg/ml.

The injectable material of (IV), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about150 or less mg/ml.

The composition of (V) or (VI), wherein the ratio of PLA to PLGA-PEG inthe first microparticle is between about 105/1 to about 80/10.

The composition of (V) or (VI), wherein the ratio of PLA to PLGA-PEG inthe first microparticle is between about 100/1.

The composition of (V), wherein the ratio of PLGA to PLGA-PEG in thesecond microparticle is between about 105/1 to about 80/10.

The composition of (V), wherein the ratio of PLGA to PLGA-PEG in thesecond microparticle is between about 100/1.

The composition of (V), (VI), or (VII), wherein the PLGA-PEG isPLGA45k-PEG5k.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is between about 1/99 to 99/1.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 99/1.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 95/5.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 90/10.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 85/15.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 80/20.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 75/25.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 70/30.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 65/35.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 60/40.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 55/45.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 50/50.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 45/55.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 40/60.

The composition of (V), (VI), or (VII), wherein the ratio of firstmicroparticles to second microparticles is about 1/99.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 90/10/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 85/15/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 80/20/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 75/25/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 70/30/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 65/35/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 60/40/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 55/45/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 50/50/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 45/55/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 40/60/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 35/65/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 30/70/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 25/75/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 20/80/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 15/85/1.

The composition of (VI) or (VII), wherein the ratio of PLA/PLGA/PLGA-PEGin the second microparticle is 10/90/1.

The composition of (V), (VI) or (VII), wherein the PLGA is acidend-capped.

The composition of (V), (VI) or (VII), wherein the PLGA is esterend-capped.

The composition of (V), (VI) or (VII), wherein the PLA is acidend-capped.

The composition of (V), (VI) or (VII), wherein the PLA is esterend-capped.

The composition of (V), (VI) or (VII), wherein the microparticles aresurface-modified.

The composition of (V), (VI) or (VII), wherein the therapeutic agent isa pharmaceutical drug.

The composition of (V), (VI) or (VII), wherein the therapeutic agent isan prodrug as described herein.

The composition of (V), (VI) or (VII), wherein the therapeutic agent issunitinib or a pharmaceutically acceptable salt thereof.

The composition of (V), (VI) or (VII), wherein the therapeutic agent issunitinib malate.

The composition of (V), (VI) or (VII), wherein the therapeutic agent isselected from Tivosinib, Imatinib, Gefitinib, and Erlotinib.

The composition of (V), (VI) or (VII), wherein the therapeutic agent isselected from Lapatinib, Canertinib, Semaxinib, and Vatalaninib,

The composition of (V), (VI) or (VII), wherein the therapeutic agent isselected from Sorafenib, Axitinib, Pazopanib, and Dasatinib.

The composition of (V), (VI) or (VII), wherein the therapeutic agent isselected from Nilotinib, Crizotinib, Ruxolitinib, Vandetanib, andVemurafenib.

The composition of (V), (VI) or (VII), wherein the therapeutic agent isselected from Bosutinib, Cabozantinib, Regorafenib, Vismodegib, andPonatinib.

The composition of (V), (VI) or (VII), wherein the therapeutic agent isselected furosemide, bumetanide, piretanide, ethacrynic acid, etozolin,and ozolinone.

The composition of (V), (VI) or (VII), wherein the microparticles have amean diameter between about 20 and 30 μm.

The composition of (V), (VI) or (VII), wherein the microparticles have amean diameter between about 20 and 50 μm.

The composition of (V), (VI) or (VII), wherein the microparticles have amean diameter between about 25 and 35 μm.

The composition of (V), (VI) or (VII), wherein the microparticles have amean diameter between about 20 and 40 μm.

The composition of (V), (VI) or (VII), wherein the microparticles have amean diameter between about 25 and 40 μm.

The injectable material of (VIII), wherein the injectable materialcomprises a compound that inhibits aggregation of the microparticlesprior to injection.

The injectable material of (VIII), wherein the injectable materialcomprises a sugar.

The injectable material of (VIII), wherein the injectable materialcomprises mannitol, sucrose, trehalose, glucose, or lactose.

The injectable material of (VIII), wherein the injectable materialcomprises a viscosity enhancer.

The injectable material of (VIII), wherein the injectable materialcomprises hyaluronic acid.

The injectable material of (VIII), wherein the injectable materialcomprises sodium hyaluronate.

The injectable material of (VIII), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about100-600 mg/ml.

The injectable material of (VIII), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about500 or less mg/ml.

The injectable material of (VIII), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about300 or less mg/ml.

The injectable material of (VIII), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about200 or less mg/ml.

The injectable material of (VIII), wherein the injectable material has arange of concentration of the solid aggregating microparticles of about150 or less mg/ml.

V. Examples of Disorders to be Treated

In one embodiment, the microparticles described herein and apharmaceutically active compound encapsulated in the microparticleoptionally in combination with a pharmaceutically acceptable carrier,excipient, or diluent are used for the treatment of a disorder,including a human disorder. In one embodiment, the composition is apharmaceutical composition for treating an eye disorder or eye disease.

Non-limiting exemplary eye disorders or diseases treatable with thecomposition include age related macular degeneration, alkaline erosivekeratoconjunctivitis, allergic conjunctivitis, allergic keratitis,anterior uveitis, Behcet's disease, blepharitis, blood-aqueous barrierdisruption, chorioiditis, chronic uveitis, conjunctivitis, contactlens-induced keratoconjunctivitis, corneal abrasion, corneal trauma,corneal ulcer, crystalline retinopathy, cystoid macular edema,dacryocystitis, diabetic keratopathy, diabetic macular edema, diabeticretinopathy, dry eye disease, dry age-related macular degeneration,eosinophilic granuloma, episcleritis, exudative macular edema, Fuchs'Dystrophy, giant cell arteritis, giant papillary conjunctivitis,glaucoma, glaucoma surgery failure, graft rejection, herpes zoster,inflammation after cataract surgery, iridocorneal endothelial syndrome,iritis, keratoconjunctivitis sicca, keratoconjunctivitis inflammatorydisease, keratoconus, lattice dystrophy, map-dot-fingerprint dystrophy,necrotic keratitis, neovascular diseases involving the retina, uvealtract or cornea, for example, neovascular glaucoma, cornealneovascularization, neovascularization resulting following a combinedvitrectomy and lensectomy, neovascularization of the optic nerve, andneovascularization due to penetration of the eye or contusive ocularinjury, neuroparalytic keratitis, non-infectious uveitis ocular herpes,ocular lymphoma, ocular rosacea, ophthalmic infections, ophthalmicpemphigoid, optic neuritis, panuveitis, papillitis, pars planitis,persistent macular edema, phacoanaphylaxis, posterior uveitis,post-operative inflammation, proliferative diabetic retinopathy,proliferative sickle cell retinopathy, proliferative vitreoretinopathy,retinal artery occlusion, retinal detachment, retinal vein occlusion,retinitis pigmentosa, retinopathy of prematurity, rubeosis iritis,scleritis, Stevens-Johnson syndrome, sympathetic ophthalmia, temporalarteritis, thyroid associated ophthalmopathy, uveitis, vernalconjunctivitis, vitamin A insufficiency-induced keratomalacia, vitritis,and wet age-related macular degeneration.

VI. Therapeutically Active Agents to be Delivered

A wide variety of therapeutic agents can be delivered in a long termsustained manner in vivo using the present invention.

A “therapeutically effective amount” of a pharmaceuticalcomposition/combination of this invention means an amount effective,when administered to a patient, to provide a therapeutic benefit such asan amelioration of symptoms of the selected disorder, typically anocular disorder. In certain aspects, the disorder is glaucoma, adisorder mediated by carbonic anhydrase, a disorder or abnormalityrelated to an increase in intraocular pressure (IOP), a disordermediated by nitric oxide synthase (NOS), a disorder requiringneuroprotection such as to regenerate/repair optic nerves, allergicconjunctivitis, anterior uveitis, cataracts, dry or wet age-relatedmacular degeneration (AMD), or diabetic retinopathy.

A “pharmaceutically acceptable salt” is formed when a therapeuticallyactive compound is modified by making an inorganic or organic,non-toxic, acid or base addition salt thereof. Salts can be synthesizedfrom a parent compound that contains a basic or acidic moiety byconventional chemical methods. Generally, such a salt can be prepared byreacting a free acid form of the compound with a stoichiometric amountof the appropriate base (such as Na, Ca, Mg, or K hydroxide, carbonate,bicarbonate, or the like), or by reacting a free base form of thecompound with a stoichiometric amount of the appropriate acid. Suchreactions are typically carried out in water or in an organic solvent,or in a mixture of the two. Generally, non-aqueous media like ether,ethyl acetate, ethanol, isopropanol, or acetonitrile are typical, wherepracticable. Examples of pharmaceutically acceptable salts include, butare not limited to, mineral or organic acid salts of basic residues suchas amines; alkali or organic salts of acidic residues such as carboxylicacids; and the like. The pharmaceutically acceptable salts include theconventional non-toxic salts and the quaternary ammonium salts of theparent compound formed, for example, from non-toxic inorganic or organicacids. For example, conventional non-toxic acid salts include thosederived from inorganic acids such as hydrochloric, hydrobromic,sulfuric, sulfamic, phosphoric, nitric and the like; and the saltsprepared from organic acids such as acetic, propionic, succinic,glycolic, stearic, lactic, malic, tartaric, citric, ascorbic, pamoic,maleic, hydroxymaleic, phenylacetic, glutamic, benzoic, salicylic,mesylic, esylic, besylic, sulfanilic, 2-acetoxybenzoic, fumaric,toluenesulfonic, methanesulfonic, ethane disulfonic, oxalic, isethionic,HOOC—(CH₂)_(n)—COOH where n is 0-4, and the like. Lists of additionalsuitable salts may be found, e.g., in Remington's PharmaceuticalSciences, 17th ed., Mack Publishing Company, Easton, Pa., p. 1418(1985).

In one embodiment, the microparticles of the present invention cancomprise a compound for the treatment of glaucoma, for instance abeta-adrenergic antagonists, a prostaglandin analog, an adrenergicagonist, a carbonic anhydrase inhibitor, a parasympathomimetic agent, adual anti-VEGF/Anti-PDGF therapeutic or a dual leucine zipper kinase(DLK) inhibitor. In another embodiment, the microparticles of thepresent invention can comprise a compound for the treatment of diabeticretinopathy. Such compounds may be administered in lower doses accordingto the invention as they may be administered at the site of the oculardisease.

Examples of loop diuretics include furosemide, bumetanide, piretanide,ethacrynic acid, etozolin, and ozolinone.

Examples of beta-adrenergic antagonists include, but are not limited to,timolol (Timoptic®), levobunolol (Betagan®), carteolol (Ocupress®),Betaxolol (Betoptic), and metipranolol (OptiPranolol®).

Examples of prostaglandin analogs include, but are not limited to,latanoprost (Xalatan®), travoprost (Travatan®), bimatoprost (Lumigan®)and tafluprost (Zioptan™).

Examples of adrenergic agonists include, but are not limited to,brimonidine (Alphagan®), epinephrine, dipivefrin (Propine®) andapraclonidine (Lopidine®).

Examples of carbonic anhydrase inhibitors include, but are not limitedto, dorzolamide (Trusopt®), brinzolamide (Azopt®), acetazolamide(Diamox®) and methazolamide (Neptazane®), see structures below:

Examples of tyrosine kinase inhibitors include Tivosinib, Imatinib,Gefitinib, Erlotinib, Lapatinib, Canertinib, Semaxinib, Vatalaninib,Sorafenib, Axitinib, Pazopanib, Dasatinib, Nilotinib, Crizotinib,Ruxolitinib, Vandetanib, Vemurafenib, Bosutinib, Cabozantinib,Regorafenib, Vismodegib, and Ponatinib. In one embodiment, the tyrosinekinase inhibitor is selected from Tivosinib, Imatinib, Gefitinib, andErlotinib. In one embodiment, the tyrosine kinase inhibitor is selectedfrom Lapatinib, Canertinib, Semaxinib, and Vatalaninib. In oneembodiment, the tyrosine kinase inhibitor is selected from Sorafenib,Axitinib, Pazopanib, and Dasatinib. In one embodiment, the tyrosinekinase inhibitor is selected from Nilotinib, Crizotinib, Ruxolitinib,Vandetanib, and Vemurafenib. In one embodiment, the tyrosine kinaseinhibitor is selected from Bosutinib, Cabozantinib, Regorafenib,Vismodegib, and Ponatinib.

An example of a parasympathomimetic includes, but is not limited to,pilocarpine.

DLK inhibitors include, but are not limited to, Crizotinib, KW-2449 andTozasertib, see structure below.

Drugs used to treat diabetic retinopathy include, but are not limitedto, ranibizumab (Lucentis®).

In one embodiment, the dual anti-VEGF/Anti-PDGF therapeutic is sunitinibmalate (Sutent®).

In one embodiment, the compound is a treatment for glaucoma and can beused as an effective amount to treat a host in need of glaucomatreatment.

In another embodiment, the compound acts through a mechanism other thanthose associated with glaucoma to treat a disorder described herein in ahost, typically a human.

In one embodiment, the therapeutic agent is selected from aphosphoinositide 3-kinase (PI3K) inhibitor, a Bruton's tyrosine kinase(BTK) inhibitor, or a spleen tyrosine kinase (Syk) inhibitor, or acombination thereof.

PI3K inhibitors that may be used in the present invention are wellknown. Examples of PI3 kinase inhibitors include but are not limited toWortmannin, demethoxyviridin, perifosine, idelalisib, Pictilisib,Palomid 529, ZSTK474, PWT33597, CUDC-907, and AEZS-136, duvelisib,GS-9820, BKM120, GDC-0032 (Taselisib)(2-[4-[2-(2-Isopropyl-5-methyl-1,2,4-triazol-3-yl)-5,6-dihydroimidazo[1,2-d][1,4]benzoxazepin-9-yl]pyrazol-1-yl]-2-methylpropanamide),MLN-1117 ((2R)-1-Phenoxy-2-butanyl hydrogen (S)-methylphosphonate; orMethyl(oxo) {[(2R)-1-phenoxy-2-butanyl]oxy}phosphonium)), BYL-719((2S)-N1-[4-Methyl-5-[2-(2,2,2-trifluoro-1,1-dimethylethyl)-4-pyridinyl]-2-thiazolyl]-1,2-pyrrolidinedicarboxamide),GSK2126458(2,4-Difluoro-N-{2-(methyloxy)-5-[4-(4-pyridazinyl)-6-quinolinyl]-3-pyridinyl}benzenesulfonamide)(omipalisib), TGX-221((±)-7-Methyl-2-(morpholin-4-yl)-9-(1-phenylaminoethyl)-pyrido[1,2-a]-pyrimidin-4-one),GSK2636771(2-Methyl-1-(2-methyl-3-(trifluoromethyl)benzyl)-6-morpholino-1H-benzo[d]imidazole-4-carboxylicacid dihydrochloride), KIN-193((R)-2-((1-(7-methyl-2-morpholino-4-oxo-4H-pyrido[1,2-a]pyrimidin-9-yl)ethyl)amino)benzoicacid), TGR-1202/RP5264, GS-9820((S)-1-(4-((2-(2-aminopyrimidin-5-yl)-7-methyl-4-mohydroxypropan-1-one),GS-1101(5-fluoro-3-phenyl-2-([S)]-1-[9H-purin-6-ylamino]-propyl)-3H-quinazolin-4-one),AMG-319, GSK-2269557, SAR245409(N-(4-(N-(3-((3,5-dimethoxyphenyl)amino)quinoxalin-2-yl)sulfamoyl)phenyl)-3-methoxy-4methylbenzamide), BAY80-6946(2-amino-N-(7-methoxy-8-(3-morpholinopropoxy)-2,3-dihydroimidazo[1,2-c]quinaz),AS 252424(5-[1-[5-(4-Fluoro-2-hydroxy-phenyl)-furan-2-yl]-meth-(Z)-ylidene]-thiazolidine-2,4-dione),CZ 24832(5-(2-amino-8-fluoro-[1,2,4]triazolo[1,5-a]pyridin-6-yl)-N-tert-butylpyridine-3-sulfonamide),Buparlisib(5-[2,6-Di(4-morpholinyl)-4-pyrimidinyl]-4-(trifluoromethyl)-2-pyridinamine),GDC-0941(2-(1H-Indazol-4-yl)-6-[[4-(methylsulfonyl)-1-piperazinyl]methyl]-4-(4-morpholinyl)thieno[3,2-d]pyrimidine),GDC-0980((S)-1-(4-((2-(2-aminopyrimidin-5-yl)-7-methyl-4-morpholinothieno[3,2-d]pyrimidin-6yl)methyl)piperazin-1-yl)-2-hydroxypropan-1-one (also known as RG7422)),SF1126((8S,14S,17S)-14-(carboxymethyl)-8-(3-guanidinopropyl)-17-(hydroxymethyl)-3,6,9,12,15-pentaoxo-1-(4-(4-oxo-8-phenyl-4H-chromen-2-yl)morpholino-4-ium)-2-oxa-7,10,13,16-tetraazaoctadecan-18-oate),PF-05212384(N-[4-[[4-(Dimethylamino)-1-piperidinyl]carbonyl]phenyl]-N′-[4-(4,6-di-4-morpholinyl-1,3,5-triazin-2-yl)phenyl]urea)(gedatolisib), LY3023414, BEZ235(2-Methyl-2-{4-[3-methyl-2-oxo-8-(quinolin-3-yl)-2,3-dihydro-1H-imidazo[4,5-c]quinolin-1-yl]phenyl}propanenitrile)(dactolisib), XL-765(N-(3-(N-(3-(3,5-dimethoxyphenylamino)quinoxalin-2-yl)sulfamoyl)phenyl)-3-methoxy-4-methylbenzamide),and GSK1059615(5-[[4-(4-Pyridinyl)-6-quinolinyl]methylene]-2,4-thiazolidenedione),PX886([(3aR,6E,9S,9aR,10R,11aS)-6-[[bis(prop-2-enyl)amino]methylidene]-5-hydroxy-9-(methoxymethyl)-9a,11a-dimethyl-1,4,7-trioxo-2,3,3a,9,10,11-hexahydroindeno[4,5h]isochromen-10-yl]acetate (also known as sonolisib)), LY294002, AZD8186, PF-4989216,pilaralisib, GNE-317, PI-3065, PI-103, NU7441 (KU-57788), HS 173,VS-5584 (SB2343), CZC24832, TG100-115, A66, YM201636, CAY10505, PIK-75,PIK-93, AS-605240, BGT226 (NVP-BGT226), AZD6482, voxtalisib, alpelisib,IC-87114, TGI100713, CH5132799, PKI-402, copanlisib (BAY 80-6946), XL147, PIK-90, PIK-293, PIK-294, 3-MA (3-methyladenine), AS-252424,AS-604850, apitolisib (GDC-0980; RG7422), and the structure described inWO2014/071109 having the formula:

BTK inhibitors for use in the present invention are well known. Examplesof BTK inhibitors include ibrutinib (also known asPCI-32765)(Imbruvica™)(1-[(3R)-3-[4-amino-3-(4-phenoxy-phenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidin-1-yl]prop-2-en-1-one),dianilinopyrimidine-based inhibitors such as AVL-101 and AVL-291/292(N-(3-((5-fluoro-2-((4-(2-methoxyethoxy)phenyl)amino)pyrimidin-4-yl)amino)phenyl)acrylamide)(Avila Therapeutics) (US Patent publication No 2011/0117073,incorporated herein in its entirety), Dasatinib([N-(2-chloro-6-methylphenyl)-2-(6-(4-(2-hydroxyethyl)piperazin-1-yl)-2-methylpyrimidin-4-ylamino)thiazole-5-carboxamide],LFM-A13 (alpha-cyano-beta-hydroxy-beta-methyl-N-(2,5-ibromophenyl)propenamide), GDC-0834([R—N-(3-(6-(4-(1,4-dimethyl-3-oxopiperazin-2-yl)phenylamino)-4-methyl-5-oxo-4,5-dihydropyrazin-2-yl)-2-methylphenyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-2-carboxamide],CGI-5604-(tert-butyl)-N-(3-(8-(phenylamino)imidazo[1,2-a]pyrazin-6-yl)phenyl)benzamide,CGI-1746(4-(tert-butyl)-N-(2-methyl-3-(4-methyl-6-((4-(morpholine-4-carbonyl)phenyl)amino)-5-oxo-4,5-dihydropyrazin-2-yl)phenyl)benzamide),CNX-774(4-(4-((4-((3-acrylamidophenyl)amino)-5-fluoropyrimidin-2-yl)amino)phenoxy)-N-methylpicolinamide),CTA056(7-benzyl-1-(3-(piperidin-1-yl)propyl)-2-(4-(pyridin-4-yl)phenyl)-1H-imidazo[4,5-g]quinoxalin-6(5H)-one),GDC-0834((R)—N-(3-(6-((4-(1,4-dimethyl-3-oxopiperazin-2-yl)phenyl)amino)-4-methyl-5-oxo-4,5-dihydropyrazin-2-yl)-2-methylphenyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-2-carboxamide),GDC-0837((R)—N-(3-(6-((4-(1,4-dimethyl-3-oxopiperazin-2-yl)phenyl)amino)-4-methyl-5-oxo-4,5-dihydropyrazin-2-yl)-2-methylphenyl)-4,5,6,7-tetrahydrobenzo[b]thiophene-2-carboxamide),HM-71224, ACP-196, ONO-4059 (Ono Pharmaceuticals), PRT062607(4-((3-(2H-1,2,3-triazol-2-yl)phenyl)amino)-2-(((1R,2S)-2-aminocyclohexyl)amino)pyrimidine-5-carboxamidehydrochloride), QL-47(1-(1-acryloylindolin-6-yl)-9-(1-methyl-1H-pyrazol-4-yl)benzo[h][1,6]naphthyridin-2(1H)-one),and RN486(6-cyclopropyl-8-fluoro-2-(2-hydroxymethyl-3-{1-methyl-5-[5-(4-methyl-piperazin-1-yl)-pyridin-2-ylamino]-6-oxo-1,6-dihydro-pyridin-3-yl}-phenyl)-2H-isoquinolin-1-one),and other molecules capable of inhibiting BTK activity, for examplethose BTK inhibitors disclosed in Akinleye et ah, Journal of Hematology& Oncology, 2013, 6:59, the entirety of which is incorporated herein byreference.

Syk inhibitors for use in the present invention are well known, andinclude, for example, Cerdulatinib(4-(cyclopropylamino)-2-((4-(4-(ethylsulfonyl)piperazin-1-yl)phenyl)amino)pyrimidine-5-carboxamide),entospletinib(6-(1H-indazol-6-yl)-N-(4-morpholinophenyl)imidazo[1,2-a]pyrazin-8-amine),fostamatinib([6-({5-Fluoro-2-[(3,4,5-trimethoxyphenyl)amino]-4-pyrimidinyl}amino)-2,2-dimethyl-3-oxo-2,3-dihydro-4H-pyrido[3,2-b][1,4]oxazin-4-yl]methyldihydrogen phosphate), fostamatinib disodium salt (sodium(6-((5-fluoro-2-((3,4,5-trimethoxyphenyl)amino)pyrimidin-4-yl)amino)-2,2-dimethyl-3-oxo-2H-pyrido[3,2-b][1,4]oxazin-4(3H)-yl)methylphosphate), BAY 61-3606(2-(7-(3,4-Dimethoxyphenyl)-imidazo[1,2-c]pyrimidin-5-ylamino)-nicotinamideHCl), RO9021(6-[(1R,2S)-2-Amino-cyclohexylamino]-4-(5,6-dimethyl-pyridin-2-ylamino)-pyridazine-3-carboxylicacid amide), imatinib (Gleevac;4-[(4-methylpiperazin-1-yl)methyl]-N-(4-methyl-3-{[4-(pyridin-3-yl)pyrimidin-2-yl]amino}phenyl)benzamide),staurosporine, GSK143(2-(((3R,4R)-3-aminotetrahydro-2H-pyran-4-yl)amino)-4-(p-tolylamino)pyrimidine-5-carboxamide),PP2(1-(tert-butyl)-3-(4-chlorophenyl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine),PRT-060318(2-(((1R,2S)-2-aminocyclohexyl)amino)-4-(m-tolylamino)pyrimidine-5-carboxamide),PRT-062607(4-((3-(2H-1,2,3-triazol-2-yl)phenyl)amino)-2-(((1R,2S)-2-aminocyclohexyl)amino)pyrimidine-5-carboxamidehydrochloride), R112(3,3′-((5-fluoropyrimidine-2,4-diyl)bis(azanediyl))diphenol), R348(3-Ethyl-4-methylpyridine), R406(6-((5-fluoro-2-((3,4,5-trimethoxyphenyl)amino)pyrimidin-4-yl)amino)-2,2-dimethyl-2H-pyrido[3,2-b][1,4]oxazin-3(4H)-one),piceatannol (3-Hydroxyresveratol), YM193306 (Singh et al. Discovery andDevelopment of Spleen Tyrosine Kinase (SYK) Inhibitors, J. Med. Chem.2012, 55, 3614-3643), 7-azaindole, piceatannol, ER-27319 (Singh et al.Discovery and Development of Spleen Tyrosine Kinase (SYK) Inhibitors, J.Med. Chem. 2012, 55, 3614-3643 incorporated in its entirety herein),Compound D (Singh et al. Discovery and Development of Spleen TyrosineKinase (SYK) Inhibitors, J. Med. Chem. 2012, 55, 3614-3643 incorporatedin its entirety herein), PRT060318 (Singh et al. Discovery andDevelopment of Spleen Tyrosine Kinase (SYK) Inhibitors, J. Med. Chem.2012, 55, 3614-3643 incorporated in its entirety herein), luteolin(Singh et al. Discovery and Development of Spleen Tyrosine Kinase (SYK)Inhibitors, J. Med. Chem. 2012, 55, 3614-3643 incorporated in itsentirety herein), apigenin (Singh et al. Discovery and Development ofSpleen Tyrosine Kinase (SYK) Inhibitors, J. Med. Chem. 2012, 55,3614-3643 incorporated in its entirety herein), quercetin (Singh et al.Discovery and Development of Spleen Tyrosine Kinase (SYK) Inhibitors, J.Med. Chem. 2012, 55, 3614-3643 incorporated in its entirety herein),fisetin (Singh et al. Discovery and Development of Spleen TyrosineKinase (SYK) Inhibitors, J. Med. Chem. 2012, 55, 3614-3643 incorporatedin its entirety herein), myricetin (Singh et al. Discovery andDevelopment of Spleen Tyrosine Kinase (SYK) Inhibitors, J. Med. Chem.2012, 55, 3614-3643 incorporated in its entirety herein), morin (Singhet al. Discovery and Development of Spleen Tyrosine Kinase (SYK)Inhibitors, J. Med. Chem. 2012, 55, 3614-3643 incorporated in itsentirety herein).

In one embodiment, the therapeutic agent is a MEK inhibitor. MEKinhibitors for use in the present invention are well known, and include,for example, trametinib/GSK1120212(N-(3-{3-Cyclopropyl-5-[(2-fluoro-4-iodophenyl)amino]-6,8-dimethyl-2,4,7-trioxo-3,4,6,7-tetrahydropyrido[4,3-d]pyrimidin-1(2H-yl}phenyl)acetamide),selumetinib(6-(4-bromo-2-chloroanilino)-7-fluoro-N-(2-hydroxyethoxy)-3-methylbenzimidazole-5-carboxamide),pimasertib/AS703026/MSC 1935369((S)—N-(2,3-dihydroxypropyl)-3-((2-fluoro-4-iodophenyl)amino)isonicotinamide),XL-518/GDC-0973(1-({3,4-difluoro-2-[(2-fluoro-4-iodophenyl)amino]phenyl}carbonyl)-3-[(2S)-piperidin-2-yl]azetidin-3-ol),refametinib/BAY869766/RDEA1 19(N-(3,4-difluoro-2-(2-fluoro-4-iodophenylamino)-6-methoxyphenyl)-1-(2,3-dihydroxypropyl)cyclopropane-1-sulfonamide),PD-0325901(N-[(2R)-2,3-Dihydroxypropoxy]-3,4-difluoro-2-[(2-fluoro-4-iodophenyl)amino]-benzamide),TAK733((R)-3-(2,3-Dihydroxypropyl)-6-fluoro-5-(2-fluoro-4-iodophenylamino)-8-methylpyrido[2,3-d]pyrimidine-4,7(3H,8H)-dione),MEK162/ARRY438162(5-[(4-Bromo-2-fluorophenyl)amino]-4-fluoro-N-(2-hydroxyethoxy)-1-methyl-1H-benzimidazole-6-carboxamide),R05126766(3-[[3-Fluoro-2-(methylsulfamoylamino)-4-pyridyl]methyl]-4-methyl-7-pyrimidin-2-yloxychromen-2-one),WX-554, R04987655/CH4987655(3,4-difluoro-2-((2-fluoro-4-iodophenyl)amino)-N-(2-hydroxyethoxy)-5-((3-oxo-1,2-oxazinan-2yl)methyl)benzamide),or AZD8330 (2-((2-fluoro-4-iodophenyl)amino)-N-(2 hydroxyethoxy)-1,5-dimethyl-6-oxo-1,6-dihydropyridine-3-carboxamide), U0126-EtOH,PD184352 (CI-1040), GDC-0623, BI-847325, cobimetinib, PD98059, BIX02189, BIX 02188, binimetinib, SL-327, TAK-733, PD318088, and additionalMEK inhibitors as described below.

In one embodiment, the therapeutic agent is a Raf inhibitor. Rafinhibitors for use in the present invention are well known, and include,for example, Vemurafinib(N-[3-[[5-(4-Chlorophenyl)-1H-pyrrolo[2,3-b]pyridin-3-yl]carbonyl]-2,4-difluorophenyl]-1-propanesulfonamide),sorafenib tosylate(4-[4-[[4-chloro-3-(trifluoromethyl)phenyl]carbamoylamino]phenoxy]-N-methylpyridine-2-carboxamide;4-methylbenzenesulfonate), AZ628(3-(2-cyanopropan-2-yl)-N-(4-methyl-3-(3-methyl-4-oxo-3,4-dihydroquinazolin-6-ylamino)phenyl)benzamide),NVP-BHG712(4-methyl-3-(1-methyl-6-(pyridin-3-yl)-1H-pyrazolo[3,4-d]pyrimidin-4-ylamino)-N-(3-(trifluoromethyl)phenyl)benzamide),RAF-265(1-methyl-5-[2-[5-(trifluoromethyl)-1H-imidazol-2-yl]pyridin-4-yl]oxy-N-[4-(trifluoromethyl)phenyl]benzimidazol-2-amine),2-Bromoaldisine(2-Bromo-6,7-dihydro-1H,5H-pyrrolo[2,3-c]azepine-4,8-dione), Raf KinaseInhibitor IV(2-chloro-5-(2-phenyl-5-(pyridin-4-yl)-1H-imidazol-4-yl)phenol),Sorafenib N-Oxide(4-[4-[[[[4-Chloro-3(trifluoroMethyl)phenyl]aMino]carbonyl]aMino]phenoxy]-N-Methyl-2pyridinecarboxaMide1-Oxide), PLX-4720, dabrafenib (GSK2118436), GDC-0879, RAF265, AZ 628,SB590885, ZM336372, GW5074, TAK-632, CEP-32496, LY3009120, and GX818(Encorafenib).

In one embodiment, the therapeutic agent is a programmed death protein 1(PD-1) inhibitor, a programmed death protein ligand 1 (PDL1) inhibitor,or a programmed death protein ligand 2 (PDL2) inhibitor. PD-1, PDL1, andPDL2 inhibitors are known in the art, and include, for example,nivolumab (BMS), pembrolizumab (Merck), pidilizumab (CureTech/Teva),AMP-244 (Amplimmune/GSK), BMS-936559 (BMS), and MEDI4736(Roche/Genentech), and MPDL3280A (Genentech).

In one embodiment, a therapeutic agent can be administered in asustained fashion.

In one embodiment, the therapeutic agent is a monoclonal antibody (MAb).Some MAbs stimulate an immune response that destroys cancer cells.Similar to the antibodies produced naturally by B cells, these MAbs“coat” the cancer cell surface, triggering its destruction by the immunesystem. For example, bevacizumab targets vascular endothelial growthfactor (VEGF), a protein secreted by tumor cells and other cells in thetumor's microenvironment that promotes the development of tumor bloodvessels. When bound to bevacizumab, VEGF cannot interact with itscellular receptor, preventing the signaling that leads to the growth ofnew blood vessels. Similarly, cetuximab and panitumumab target theepidermal growth factor receptor (EGFR), and trastuzumab targets thehuman epidermal growth factor receptor 2 (HER-2). MAbs that bind to cellsurface growth factor receptors prevent the targeted receptors fromsending their normal growth-promoting signals. They may also triggerapoptosis and activate the immune system to destroy tumor cells.

Other agents may include, but are not limited to, at least one oftamoxifen, midazolam, letrozole, bortezomib, anastrozole, goserelin, anmTOR inhibitor, a PI3 kinase inhibitor as described above, a dualmTOR-PI3K inhibitor, a MEK inhibitor, a RAS inhibitor, ALK inhibitor, anHSP inhibitor (for example, HSP70 and HSP 90 inhibitor, or a combinationthereof), a BCL-2 inhibitor as described above, apopototic inducingcompounds, an AKT inhibitor, including but not limited to, MK-2206,GSK690693, Perifosine, (KRX-0401), GDC-0068, Triciribine, AZD5363,Honokiol, PF-04691502, and Miltefosine, a PD-1 inhibitor as describedabove including but not limited to, Nivolumab, CT-011, MK-3475,BMS936558, and AMP-514 or a FLT-3 inhibitor, including but not limitedto, P406, Dovitinib, Quizartinib (AC220), Amuvatinib (MP-470),Tandutinib (MLN518), ENMD-2076, and KW-2449, or a combination thereof.Examples of mTOR inhibitors include but are not limited to rapamycin andits analogs, everolimus (Afinitor), temsirolimus, ridaforolimus,sirolimus, and deforolimus. Examples of MEK inhibitors include but arenot limited to tametinib/GSK1120212(N-(3-{3-Cyclopropyl-5-[(2-fluoro-4-iodophenyl)amino]-6,8-dimethyl-2,4,7-trioxo-3,4,6,7-tetrahydropyrido[4,3-d]pyrimidin-1(2H-yl}phenyl)acetamide),selumetinob(6-(4-bromo-2-chloroanilino)-7-fluoro-N-(2-hydroxyethoxy)-3-methylbenzimidazole-5-carboxamide),pimasertib/AS703026/MSC1935369((S)—N-(2,3-dihydroxypropyl)-3-((2-fluoro-4-iodophenyl)amino)isonicotinamide),XL-518/GDC-0973(1-({3,4-difluoro-2-[(2-fluoro-4-iodophenyl)amino]phenyl}carbonyl)-3-[(2S)-piperidin-2-yl]azetidin-3-ol)(cobimetinib), refametinib/BAY869766/RDEA119(N-(3,4-difluoro-2-(2-fluoro-4-iodophenylamino)-6-methoxyphenyl)-1-(2,3-dihydroxypropyl)cyclopropane-1-sulfonamide),PD-0325901(N-[(2R)-2,3-Dihydroxypropoxy]-3,4-difluoro-2-[(2-fluoro-4-iodophenyl)amino]-benzamide),TAK733((R)-3-(2,3-Dihydroxypropyl)-6-fluoro-5-(2-fluoro-4-iodophenylamino)-8-methylpyrido[2,3d]pyrimidine-4,7(3H,8H)-dione),MEK162/ARRY438162(5-[(4-Bromo-2-fluorophenyl)amino]-4-fluoro-N-(2-hydroxyethoxy)-1-methyl-1H-benzimidazole-6carboxamide), R05126766(3-[[3-Fluoro-2-(methylsulfamoylamino)-4-pyridyl]methyl]-4-methyl-7-pyrimidin-2-yloxychromen-2-one),WX-554, R04987655/CH4987655(3,4-difluoro-2-((2-fluoro-4-iodophenyl)amino)-N-(2-hydroxyethoxy)-5-((3-oxo-1,2-oxazinan-2yl)methyl)benzamide), or AZD8330(2-((2-fluoro-4-iodophenyl)amino)-N-(2-hydroxyethoxy)-1,5-dimethyl-6-oxo-1,6-dihydropyridine-3-carboxamide).Examples of RAS inhibitors include but are not limited to Reolysin andsiG12D LODER. Examples of ALK inhibitors include but are not limited toCrizotinib, Ceritinib (Zykadia), AP26113, and LDK378. HSP inhibitorsinclude but are not limited to Geldanamycin or17-N-Allylamino-17-demethoxygeldanamycin (17AAG), and Radicicol.

In certain aspects, the therapeutic agent is an anti-inflammatory agent,a chemotherapeutic agent, a radiotherapeutic, an additional therapeuticagent, or an immunosuppressive agent.

In one embodiment, a chemotherapeutic is selected from, but not limitedto, imatinib mesylate (Gleevac®), dasatinib (Sprycel®), nilotinib(Tasigna®), bosutinib (Bosulif®), trastuzumab (Herceptin®),trastuzumab-DM1, pertuzumab (Perjeta™), lapatinib (Tykerb®), gefitinib(Iressa®), erlotinib (Tarceva®), cetuximab (Erbitux®), panitumumab(Vectibix®), vandetanib (Caprelsa®), vemurafenib (Zelboraf®), vorinostat(Zolinza®), romidepsin (Istodax®), bexarotene (Tagretin®), alitretinoin(Panretin®), tretinoin (Vesanoid®), carfilizomib (Kyprolis™),pralatrexate (Folotyn®), bevacizumab (Avastin®), ziv-aflibercept(Zaltrap®), sorafenib (Nexavar®), sunitinib (Sutent®), pazopanib(Votrient®), regorafenib (Stivarga®), and cabozantinib (Cometriq™).

Additional chemotherapeutic agents include, but are not limited to, aradioactive molecule, a toxin, also referred to as cytotoxin orcytotoxic agent, which includes any agent that is detrimental to theviability of cells, and liposomes or other vesicles containingchemotherapeutic compounds. General anticancer pharmaceutical agentsinclude: vincristine (Oncovin®) or liposomal vincristine (Marqibo®),daunorubicin (daunomycin or Cerubidine®) or doxorubicin (Adriamycin®),cytarabine (cytosine arabinoside, ara-C, or Cytosar®), L-asparaginase(Elspar®) or PEG-L-asparaginase (pegaspargase or Oncaspar®), etoposide(VP-16), teniposide (Vumon®), 6-mercaptopurine (6-MP or Purinethol®),Methotrexate, cyclophosphamide (Cytoxan®), Prednisone, dexamethasone(Decadron), imatinib (Gleevec®), dasatinib (Sprycel®), nilotinib(Tasigna®), bosutinib (Bosulif®), and ponatinib (Iclusig™). Examples ofadditional suitable chemotherapeutic agents include but are not limitedto 1-dehydrotestosterone, 5-fluorouracil decarbazine, 6-mercaptopurine,6-thioguanine, actinomycin D, adriamycin, aldesleukin, an alkylatingagent, allopurinol sodium, altretamine, amifostine, anastrozole,anthramycin (AMC)), an anti-mitotic agent, cis-dichlorodiamine platinum(II) (DDP) cisplatin), diamino dichloro platinum, anthracycline, anantibiotic, an antimetabolite, asparaginase, BCG live (intravesical),betamethasone sodium phosphate and betamethasone acetate, bicalutamide,bleomycin sulfate, busulfan, calcium leucouorin, calicheamicin,capecitabine, carboplatin, lomustine (CCNU), carmustine (BSNU),chlorambucil, cisplatin, cladribine, colchicin, conjugated estrogens,cyclophosphamide, cyclothosphamide, cytarabine, cytarabine, cytochalasinB, cytoxan, dacarbazine, dactinomycin, dactinomycin (formerlyactinomycin), daunirubicin HCL, daunorucbicin citrate, denileukindiftitox, Dexrazoxane, Dibromomannitol, dihydroxy anthracin dione,docetaxel, dolasetron mesylate, doxorubicin HCL, dronabinol, E. coliL-asparaginase, emetine, epoetin-α, Erwinia L-asparaginase, esterifiedestrogens, estradiol, estramustine phosphate sodium, ethidium bromide,ethinyl estradiol, etidronate, etoposide citrororum factor, etoposidephosphate, filgrastim, floxuridine, fluconazole, fludarabine phosphate,fluorouracil, flutamide, folinic acid, gemcitabine HCL, glucocorticoids,goserelin acetate, gramicidin D, granisetron HCL, hydroxyurea,idarubicin HCL, ifosfamide, interferon α-2b, irinotecan HCL, letrozole,leucovorin calcium, leuprolide acetate, levamisole HCL, lidocaine,lomustine, maytansinoid, mechlorethamine HCL, medroxyprogesteroneacetate, megestrol acetate, melphalan HCL, mercaptipurine, mesna,methotrexate, methyltestosterone, mithramycin, mitomycin C, mitotane,mitoxantrone, nilutamide, octreotide acetate, ondansetron HCL,paclitaxel, pamidronate disodium, pentostatin, pilocarpine HCL,plimycin, polifeprosan 20 with carmustine implant, porfimer sodium,procaine, procarbazine HCL, propranolol, rituximab, sargramostim,streptozotocin, tamoxifen, taxol, teniposide, tenoposide, testolactone,tetracaine, thioepa chlorambucil, thioguanine, thiotepa, topotecan HCL,toremifene citrate, trastuzumab, tretinoin, valrubicin, vinblastinesulfate, vincristine sulfate, and vinorelbine tartrate.

Additional therapeutic agents can include bevacizumab, sutinib,sorafenib, 2-methoxyestradiol or 2ME2, finasunate, vatalanib,vandetanib, aflibercept, volociximab, etaracizumab (MEDI-522),cilengitide, erlotinib, cetuximab, panitumumab, gefitinib, trastuzumab,dovitinib, figitumumab, atacicept, rituximab, alemtuzumab, aldesleukine,atlizumab, tocilizumab, temsirolimus, everolimus, lucatumumab,dacetuzumab, HLL1, huN901-DM1, atiprimod, natalizumab, bortezomib,carfilzomib, marizomib, tanespimycin, saquinavir mesylate, ritonavir,nelfinavir mesylate, indinavir sulfate, belinostat, panobinostat,mapatumumab, lexatumumab, dulanermin, ABT-737, oblimersen, plitidepsin,talmapimod, P276-00, enzastaurin, tipifarnib, perifosine, imatinib,dasatinib, lenalidomide, thalidomide, simvastatin, celecoxib,bazedoxifene, AZD4547, rilotumumab, oxaliplatin (Eloxatin), PD0332991(palbociclib), ribociclib (LEE011), amebaciclib (LY2835219), HDM201,fulvestrant (Faslodex), exemestane (Aromasin), PIM447, ruxolitinib(INC424), BGJ398, necitumumab, pemetrexed (Alimta), and ramucirumab(IMC-1121B).

In one aspect of the present invention, an immunosuppressive agent isused, preferably selected from the group consisting of a calcineurininhibitor, e.g. a cyclosporin or an ascomycin, e.g. Cyclosporin A(NEORAL®), FK506 (tacrolimus), pimecrolimus, a mTOR inhibitor, e.g.rapamycin or a derivative thereof, e.g. Sirolimus (RAPAMUNE®),Everolimus (Certican®), temsirolimus, zotarolimus, biolimus-7,biolimus-9, a rapalog, e.g. ridaforolimus, azathioprine, campath 1H, aSiP receptor modulator, e.g. fingolimod or an analogue thereof, ananti-IL-8 antibody, mycophenolic acid or a salt thereof, e.g. sodiumsalt, or a prodrug thereof, e.g. Mycophenolate Mofetil (CELLCEPT®), OKT3(ORTHOCLONE OKT3®), Prednisone, ATGAM®, THYMOGLOBULIN®, BrequinarSodium, OKT4, T10B9.A-3A, 33B3.1, 15-deoxyspergualin, tresperimus,Leflunomide ARAVA®, CTLAI-Ig, anti-CD25, anti-IL2R, Basiliximab(SIMULECT®), Daclizumab (ZENAPAX®), mizorbine, methotrexate,dexamethasone, ISAtx-247, SDZ ASM 981 (pimecrolimus, Elidel®), CTLA4lg(Abatacept), belatacept, LFA3lg, etanercept (sold as Enbrel® byImmunex), adalimumab (Humira®), infliximab (Remicade®), an anti-LFA-1antibody, natalizumab (Antegren®), Enlimomab, gavilimomab, antithymocyteimmunoglobulin, siplizumab, Alefacept efalizumab, pentasa, mesalazine,asacol, codeine phosphate, benorylate, fenbufen, naprosyn, diclofenac,etodolac and indomethacin, aspirin and ibuprofen.

Examples of types of therapeutic agents that can be eluted from themicroparticles include anti-inflammatory drugs, antimicrobial agents,anti-angiogenesis agents, immunosuppressants, antibodies, steroids,ocular antihypertensive drugs and combinations thereof. Examples oftherapeutic agents include amikacin, anecortane acetate,anthracenedione, anthracycline, an azole, amphotericin B, bevacizumab,camptothecin, cefuroxime, chloramphenicol, chlorhexidine, chlorhexidinedigluconate, clortrimazole, a clotrimazole cephalosporin,corticosteroids, dexamethasone, desamethazone, econazole, eftazidime,epipodophyllotoxin, fluconazole, flucytosine, fluoropyrimidines,fluoroquinolines, gatifloxacin, glycopeptides, imidazoles, itraconazole,ivermectin, ketoconazole, levofloxacin, macrolides, miconazole,miconazole nitrate, moxifloxacin, natamycin, neomycin, nystatin,ofloxacin, polyhexamethylene biguanide, prednisolone, prednisoloneacetate, pegaptanib, platinum analogues, polymicin B, propamidineisethionate, pyrimidine nucleoside, ranibizumab, squalamine lactate,sulfonamides, triamcinolone, triamcinolone acetonide, triazoles,vancomycin, anti-vascular endothelial growth factor (VEGF) agents, VEGFantibodies, VEGF antibody fragments, vinca alkaloid, timolol, betaxolol,travoprost, latanoprost, bimatoprost, brimonidine, dorzolamide,acetazolamide, pilocarpine, ciprofloxacin, azithromycin, gentamycin,tobramycin, cefazolin, voriconazole, gancyclovir, cidofovir, foscarnet,diclofenac, nepafenac, ketorolac, ibuprofen, indomethacin,fluoromethalone, rimexolone, anecortave, cyclosporine, methotrexate,tacrolimus and combinations thereof.

Examples of immunosuppressive agents are calcineurin inhibitor, e.g., acyclosporin or an ascomycin, e.g., Cyclosporin A (NEORAL®), FK506(tacrolimus), pimecrolimus, a mTOR inhibitor, e.g., rapamycin or aderivative thereof, e.g., Sirolimus (RAPAMUNE®), Everolimus (Certican®),temsirolimus, zotarolimus, biolimus-7, biolimus-9, a rapalog, e.g.,ridaforolimus, azathioprine, campath 1H, a S1P receptor modulator, e.g.,fingolimod or an analogue thereof, an anti IL-8 antibody, mycophenolicacid or a salt thereof, e.g., sodium salt, or a prodrug thereof, e.g.,Mycophenolate Mofetil (CELLCEPT®), OKT3 (ORTHOCLONE OKT3®), Prednisone,ATGAM®, THYMOGLOBULIN®, Brequinar Sodium, OKT4, T10B9.A-3A, 33B3.1,15-deoxyspergualin, tresperimus, Leflunomide ARAVA®, CTLAI-Ig,anti-CD25, anti-IL2R, Basiliximab (SIMULECT®), Daclizumab (ZENAPAX®),mizorbine, methotrexate, dexamethasone, ISAtx-247, SDZ ASM 981(pimecrolimus, Elidel®), CTLA4lg (Abatacept), belatacept, LFA3lg,etanercept (sold as Enbrel® by Immunex), adalimumab (Humira®),infliximab (Remicade®), an anti-LFA-1 antibody, natalizumab (Antegren®),Enlimomab, gavilimomab, antithymocyte immunoglobulin, siplizumab,Alefacept efalizumab, pentasa, mesalazine, asacol, codeine phosphate,benorylate, fenbufen, naprosyn, diclofenac, etodolac and indomethacin,aspirin and ibuprofen.

In certain embodiments, the surface-treated microparticles of thepresent invention can comprise a prodrug as disclosed below. In all ofthe polymer moieties described in this specification, where thestructures are depicted as block copolymers (for example, blocks of “x”followed by blocks of “y”) it is intended that the polymer canalternately be a random or alternating copolymer (for example, “x” and“y”, are either randomly distributed or alternate). Unlessstereochemistry is specifically indicated, each individual moiety ofeach oligomer that has a chiral center can be presented at the chiralcarbon in (R) or (S) configuration or a mixture thereof, including aracemic mixture.

In addition, prodrug moieties that have repetitive units of the same orvarying monomers, for example including but not limited to an oligomerof polylactic acid, polylactide-coglycolide, or polypropylene oxide,that has a chiral carbon can be used with the chiral carbons all havingthe same stereochemistry, random stereochemistry (by either monomer oroligomer), racemic (by either monomer or oligomer) or ordered butdifferent stereochemistry such as a block of S enantiomer units followedby a block of R enantiomer units in each oligomeric unit. In someembodiments lactic acid is used in its naturally occurring Senantiomeric form.

Prostaglandin Prodrugs

The disclosure provides prostaglandin prodrugs of Formula IA:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

L¹ is selected from:

L² is selected from:

A is selected from: H, alkyl, cycloalkyl, cycloalkylalkyl, heterocycle,heterocycloalkyl, aryl, arylalkyl, heteroaryl, heteroarylalkyl, aryloxy,and alkyloxy wherein each group can be optionally substituted withanother desired substituent group which is pharmaceutically acceptableand sufficiently stable under the conditions of use, for exampleselected from R⁵;

R¹, R², and R³ are selected from: —C(O)R⁴, C(O)A, and hydrogen whereinin Formula IA either R¹ or R² cannot be hydrogen and wherein R¹, R², andR³ can be further optionally substituted with R⁵;

R⁴ is selected from:

-   -   (i) —C₁₀-C₃₀alkylR⁵, —C₁₀-C₃₀alkenylR⁵, —C₁₀-C₃₀alkynylR⁵,        —C₁₀-C₃₀alkenylalkynylR⁵, —C₁₀-C₃₀alkyl, —C₁₀-C₃₀alkenyl,        —C₁₀-C₃₀alkynyl, —C₁₀-C₃₀alkenylalkynyl; and    -   (ii) an unsaturated fatty acid residue including but not limited        to the carbon chains from linoleic acid        (—(CH₂)₈(CH)₂CH₂(CH)₂(CH₂)₄CH₃)), docosahexaenoic acid        (—(CH₂)₃(CHCHCH₂)₆CH₃)), eicosapentaenoic acid        (—(CH₂)₄(CHCHCH₂)₅CH₃)), alpha-linolenic acid        (—(CH₂)₈(CHCHCH₂)₃CH₃)), stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid and mead acid, and wherein, if        desired, each of which can be substituted with R⁵; and

R⁵ is selected from: halogen, hydroxyl, cyano, mercapto, amino, alkyl,alkoxy, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, heterocyclyl,heterocycloalkyl, aryl, arylalkyl, heteroaryl, heteroarylalkyl, aryloxy,—S(O)₂alkyl, —S(O)alkyl, —P(O)(Oalkyl)₂, B(OH)₂, —Si(CH₃)₃, —COOH,—COOalkyl, and —CONH₂, each of which except halogen, cyano, and—Si(CH₃)₃ may be optionally substituted, for example with halogen,alkyl, aryl, heterocycle or heteroaryl if desired and if the resultingcompound achieves the desired purpose, wherein the group cannot besubstituted with itself, for example alkyl would not be substituted withalkyl.

Non-limiting examples of R⁴ include:

wherein n, m, and o are independently selected from any integer between0 and 29 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,19, 20, 21, 22, 23, 24, 25, 26, 27, 28 or 29) wherein n+m+o is 7 to 30carbons and wherein mm is any integer between 1 and 30 (1, 2, 3, 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,25, 26, 27, 28, 29 or 30). In one embodiment mm is independentlyselected from the following ranges: 1 to 5, 6 to 11, 12 to 17, 18 to 23,and 24 to 30 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30).

In one embodiment, —C₁₀-C₃₀ as used in the definition of R⁴ is —C₁₀-C₂₈,—C₁₀-C₂₆, —C₁₀-C₂₄, —C₁₀-C₂₂, —C₁₀-C₂₀, —C₁₀-C₁₈, —C₁₀-C₁₆, —C₁₀-C₁₄, or—C₁₀-C₁₂.

Non-limiting examples of Formula IA include:

The disclosure provides prostaglandin prodrugs of Formula IIA:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R⁶ is selected from:

-   -   (i) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, and poly(lactic-co-glycolic acid)        including:

or polyglycolic acid, or a polyester, polyamide, or other biodegradablepolymer, each of which can be capped to complete the terminal valence.In some embodiments, the compound can be capped with hydrogen, or can becapped to create a terminal ester or ether. For example, the moiety canbe capped with a terminal hydroxyl or carboxy which can be furtherderivatized to an ether or ester;

-   -   (ii) —C₁₀-C₃₀alkylR⁵, —C₁₀-C₃₀alkenylR⁵, —C₁₀-C₃₀alkynylR⁵,        —C₁₀-C₃₀alkenylalkynylR⁵, —C₁₀-C₃₀alkyl, —C₁₀-C₃₀alkenyl,        —C₁₀-C₃₀alkynyl, —C₁₀-C₃₀alkenylalkynyl;    -   (iii) an unsaturated fatty acid residue including but not        limited the carbon fragment taken from linoleic acid        (—(CH₂)₈(CH)₂CH₂(CH)₂(CH₂)₄CH₃)), docosahexaenoic acid        (—(CH₂)₃(CHCHCH₂)₆CH₃)), eicosapentaenoic acid        (—(CH₂)₄(CHCHCH₂)₅CH₃)), alpha-linolenic acid        (—(CH₂)₈(CHCHCH₂)₃CH₃)) stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid or mead acid;    -   (iv) alkyl, cycloalkyl, cycloalkylalkyl, heterocycle,        heterocycloalkyl, arylalkyl, heteroarylalkyl;

wherein R⁶ can only be selected from (ii), (iii), and (iv) in FormulaIIA if at least one of R⁷ and R⁸ is selected to be R⁵⁰;

R⁷ and R⁸ are independently selected from: —C(O)R⁴, —C(O)A, hydrogen,and R⁵⁰;

R⁵⁰ is selected from carbonyl derivatives of polyethylene glycol,polypropylene glycol, polypropylene oxide, polylactic acid, andpoly(lactic-co-glycolic acid) including:

or polyglycolic acid, or a polyester, polyamide, or other biodegradablepolymer, each of which can be capped to complete the terminal valence.In some embodiments, the compound can be capped with hydrogen, or can becapped to create a terminal ester or ether. For example, the moiety canbe capped with a terminal hydroxyl or carboxy which can be furtherderivatized to an ether or ester; and

R³¹¹ is hydroxy, amino, A, alkyl, alkoxy, alkenyl, alkynyl, cycloalkyl,cycloalkylalkyl, heterocyclyl, heterocycloalkyl, aryl, arylalkyl,heteroaryl, heteroarylalkyl, aryloxy, or polyethylene glycol;

R³¹ is hydrogen, A, —COOH, —C(O)A, alkyl, alkoxy, alkenyl, alkynylcycloalkyl, cycloalkylalkyl, heterocyclyl, heterocycloalkyl, aryl,arylalkyl, heteroaryl, heteroarylalkyl, aryloxy, hydroxy, andpolyethylene glycol; and

R^(31a) is hydrogen, —C(O)alkyl, aryl, alkyl, cycloalkyl,cycloalkylalkyl, heterocyclyl, heterocycloalkyl, arylalkyl, heteroaryl,heteroarylalkyl, polylactic acid, polygylcolic acid, polyethyleneglycol, stearoyl, or

x and y are independently selected from any integer between 1 and 30 (1,2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,22, 23, 24, 25, 26, 27, 28, 29 or 30). In one embodiment x and y areindependently selected from the following ranges: 1 to 5, 6 to 11, 12 to17, 18 to 23, and 24 to 30 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or30) and in a preferred embodiment, x and y are independently selectedfrom an integer between 1 and 12 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and12);

z is independently selected from any integer between 0 and 20 (0, 1, 2,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20) andin a preferred embodiment, z is an integer between 0 and 12 (0, 1, 2, 3,4, 5, 6, 7, 8, 9, 10, 11, or 12) or between 0 and 6 (0, 1, 2, 3, 4, 5,or 6);

zz is independently selected from any integer between 1 and 20 (1, 2, 3,4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20) and ina preferred embodiment, z is an integer between 1 and 12 (1, 2, 3, 4, 5,6, 7, 8, 9, 10, 11, or 12) or between 1 and 6 (1, 2, 3, 4, 5, or 6); and

wherein all other variables are defined herein.

Non-limiting examples of R⁵⁰ include:

In one embodiment, —C₁₀-C₃₀ as used in the definition of R⁶ is —C₁₀-C₂₈,—C₁₀-C₂₆, —C₁₀-C₂₄, —C₁₀-C₂₂, —C₁₀-C₂₀, —C₁₀-C₁₈, —C₁₀-C₁₆, —C₁₀-C₁₄, or—C₁₀-C₁₂.

In one embodiment R⁶ is isopropyl.

Non-limiting examples of Formula IIA include:

The disclosure provides prostaglandin prodrugs of Formula IIIA:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

L³ is selected from:

wherein all other variables are defined herein.

In one embodiment, —C₁₀-C₃₀ as used in the definition of R⁶ is —C₁₂-C₂₈,—C₁₂-C₂₆, —C₁₂-C₂₄, —C₁₄-C₂₂, —C₁₄-C₂₀, —C₁₄-C₁₈, —C₁₄-C₁₆, or —C₁₂-C₁₄.

Non-limiting examples of Formula IIIA include:

The disclosure provides prostaglandin prodrugs of Formula IVA:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R¹¹ is selected from:

-   -   (i) R¹²;    -   (ii) —NH—C₄-C₃₀alkenyl-C(O)R¹², —NH—C₄-C₃₀alkynyl-C(O)R¹²,        —NH—C₄-C₃₀alkenylalkynyl-C(O)R¹², —NH—C₂-C₃₀alkyl-C(O)R¹²,        —O—C₄-C₃₀alkenyl-C(O)R¹², —O—C₄-C₃₀alkynyl-C(O)R¹²,        —O—C₄-C₃₀alkenylalkynyl-C(O)R¹², and —O—C₂-C₃₀alkyl-C(O)R¹²;    -   (iii) —NH—C₄-C₃₀alkenyl=R¹³, —NH—C₄-C₃₀alkynyl=R¹³,        —NH—C₄-C₃₀alkenylalkynyl=R¹³, —NH—C₂-C₃₀alkyl=R¹³,        —O—C₄-C₃₀alkenyl=R¹³, —O—C₄-C₃₀alkynyl=R¹³,        —O—C₄-C₃₀alkenylalkynyl=R¹³, —O—C₂-C₃₀alkyl=R¹³;    -   (iv) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, and poly(lactic-co-glycolic acid),        polyglycolic acid, or a polyester, polyamide, or other        biodegradable polymer, each of which is substituted with at        least one L⁴-R¹² including:

and

-   -   (v) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, and poly(lactic-co-glycolic acid),        polyglycolic acid, or a polyester, polyamide, or other        biodegradable polymer, each of which is substituted with at        least one moiety of L⁵=R¹³ including

wherein R¹¹ can be further substituted with R⁵ if valence permits, astable compound is formed, and the resulting compound ispharmaceutically acceptable;

R¹² is selected from:

R¹³ is selected from:

and

R¹⁵ is selected from R¹⁶ and R¹⁷;

R¹⁶ is selected from:

-   -   (i) —C(O)C₃-C₃₀alkylR⁵, —C(O)C₃-C₃₀alkenylR⁵,        —C(O)C₃-C₃₀alkynylR⁵, —C(O)C₃-C₃₀alkenylalkynylR⁵,        —C(O)C₃-C₃₀alkyl, —C(O)C₃-C₃₀alkenyl, —C(O)C₃-C₃₀alkynyl, and        —C(O)C₃-C₃₀alkenylalkynyl;    -   (ii) an unsaturated fatty acid residue including but not limited        the carbonyl fragment taken from linoleic acid        (—C(O)(CH₂)₇(CH)₂CH₂(CH)₂(CH₂)₄CH₃)), docosahexaenoic acid        (—C(O)(CH₂)₂(CHCHCH₂)₆CH₃)), eicosapentaenoic acid        (—C(O)(CH₂)₃(CHCHCH₂)₅CH₃)), alpha-linolenic acid        (—C(O)(CH₂)₇(CHCHCH₂)₃CH₃)) stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid and mead acid;    -   (iii) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, and poly(lactic-co-glycolic acid)        including:

or polyglycolic acid, or a polyester, polyamide, or other biodegradablepolymer, each of which can be capped to complete the terminal valence.In some embodiments, the compound can be capped with hydrogen, or can becapped to create a terminal ester or ether. For example, the moiety canbe capped with a terminal hydroxyl or carboxy which can be furtherderivatized to an ether or ester;

R¹⁷ is selected from: H and —C(O)A;

L⁴ is bond, alkyl, alkenyl, alkynyl, —C(O)—, —C(S)—, —NH—, —N(alkyl)-,—O—, or alkyl-C(O)—;

L⁵ is double bond, alkyl, or alkenyl; and

wherein all other variables are defined herein.

In one embodiment R¹¹ is selected from: —NH—C₄-C₂₉alkenyl-CH═R¹³,—NH—C₄-C₂₉alkynyl-CH═R¹³, —NH—C₄-C₂₉alkenylalkynyl-CH═R¹³,—NH—C₂-C₂₉alkyl-CH═R¹³, —O—C₄-C₂₉alkenyl-CH═R¹³,—O—C₄-C₂₉alkynyl-CH═R¹³, —O—C₄-C₂₉alkenylalkynyl-CH═R¹³, and—O—C₂-C₂₉alkyl-CH═R¹³.

In various different embodiments, —C₄-C₂₉ as used in the definition ofR¹¹ may be —C₄-C₂₈, —C₄-C₂₆, —C₄-C₂₄, —C₆-C₂₂, —C₆-C₂₀, —C₈-C₁₈,—C₈-C₁₆, —C₈-C₁₄, —C₈-C₁₂, —C₈-C₂₀, or —C₆-C₂₄.

Non-limiting examples of R¹¹ include:

wherein n, m, o, x, and y are as defined above.

Non-limiting examples of R¹⁶ include:

Non-limiting examples of Formula IVA include:

The disclosure provides prostaglandin prodrugs of Formula VA:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R¹⁰³ is selected from: H, alkyl, cycloalkyl, cycloalkylalkyl,heterocycle, heterocycloalkyl, aryl, arylalkyl, heteroaryl, andheteroarylalkyl wherein each group other than hydrogen can be optionallysubstituted with another desired substituent group which ispharmaceutically acceptable and sufficiently stable under the conditionsof use, for example selected from R⁵;

R¹⁰⁰ is selected from:

-   -   (i) C₁-C₁₀alkyl, —C₀-C₁₀alkyl(C₃-C₇cycloalkyl), heterocycle,        —C₀-C₁₀alkyl(C₃-C₇heterocycloalkyl), -arylC₀-C₁₀alkyl,        -heteroarylalkyl, —C₀-C₁₀alkylC₂-C₁₀alkenyl, and C₂-C₁₀alkynyl;    -   (ii) an unsaturated fatty acid residue including but not limited        the carbon fragment taken from linoleic acid        (—(CH₂)₈(CH)₂CH₂(CH)₂(CH₂)₄CH₃)), docosahexaenoic acid        (—(CH₂)₃(CHCHCH₂)₆CH₃)), eicosapentaenoic acid        (—(CH₂)₄(CHCHCH₂)₅CH₃)), alpha-linolenic acid        (—(CH₂)₈(CHCHCH₂)₃CH₃)) stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid and mead acid;    -   (iii) —C₁₀-C₃₀alkylR⁵, —C₁₀-C₃₀alkenylR⁵, —C₁₀-C₃₀alkynylR⁵,        —C₁₀-C₃₀alkenylalkynylR⁵, —C₁₀-C₃₀alkyl, —C₁₀-C₃₀alkenyl,        —C₁₀-C₃₀alkynyl, —C₁₀-C₃₀alkenylalkynyl; and    -   (iv) R⁵⁰;

wherein R¹⁰⁰ in Formula VA can only be selected from (i), (ii), and(iii) above if at least one of R⁷ and R⁸ is selected to be R⁵⁰; and

wherein all other variables are defined herein.

In one embodiment, —C₁₀-C₃₀ as used in the definition of R¹⁰⁰ is—C₁₂-C₂₈, —C₁₂-C₂₆, —C₁₂-C₂₄, —C₁₄-C₂₂, —C₁₄-C₂₀, —C₁₄-C₁₈, —C₁₄-C₁₆, or—C₁₂-C₁₄.

Non-limiting examples of Formula VA include:

The disclosure provides prostaglandin prodrugs of Formula VIA:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof

wherein all variables are as defined herein.

Non-limiting examples of Formula VIA include:

In one embodiment, R¹⁰⁰ is ethyl and R¹⁰³ is hydrogen.

In one embodiment, R⁵⁰ is

The disclosure provides prostaglandin prodrugs of Formula VIIA:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

L^(2′) is selected from:

B is selected from: heterocycle, heterocycloalkyl, aryl, arylalkyl,heteroaryl, heteroarylalkyl, aryloxy, and alkyloxy wherein each groupcan be optionally substituted with another desired substituent groupwhich is pharmaceutically acceptable and sufficiently stable under theconditions of use, for example selected from R⁵; and

R¹, R², and R³ are independently selected from: —C(O)R⁴, C(O)A, andhydrogen,

wherein in Formula VIIA, R¹ or R² is —C(O)R⁴;

R¹²⁴ is selected from:

-   -   (i) an unsaturated fatty acid residue containing at least 22        carbon atoms including but not limited to the carbon chains from        docosahexaenoic acid (—(CH₂)₃(CHCHCH₂)₆CH₃)), alpha-linolenic        acid (—(CH₂)₈(CHCHCH₂)₃CH₃)), docosatetraenoic acid, and        nervonic acid,    -   (ii) —C₂₂-C₃₀alkylR⁵, —C₂₂-C₃₀alkenylR⁵, —C₂₂-C₃₀alkynylR⁵,        —C₂₂-C₃₀alkenylalkynylR⁵, —C₂₂-C₃₀alkyl, —C₂₂-C₃₀alkenyl,        —C₂₂-C₃₀alkynyl, —C₂₂-C₃₀alkenylalkynyl;        -   and wherein, if desired, each R¹²⁴ can be substituted with            R⁵; and        -   wherein all other variables are defined herein.

Non-limiting examples of Formula VIIA include:

In one embodiment, —C₂₂-C₃₀ as used in the definition of R⁴ is —C₂₂-C₂₈,—C₂₂-C₂₆, or —C₂₂-C₂₄.

The disclosure provides prostaglandin prodrugs of Formula VIIIA:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R¹¹¹ is selected from:

-   -   (i) R¹⁰²;    -   (ii) —NH—C₂-C₃₀alkenyl-C(O)R¹⁰², —NH—C₂-C₃₀alkynyl-C(O)R¹⁰²,        —NH—C₂-C₃₀alkenylalkynyl-C(O)R¹⁰², —NH—C₁-C₃₀alkyl-C(O)R¹⁰²,        —O—C₂-C₃₀alkenyl-C(O)R¹⁰², —O—C₂-C₃₀alkynyl-C(O)R¹⁰²,        —O—C₂-C₃₀alkenylalkynyl-C(O)R¹⁰², and —O—C₁-C₃₀alkyl-C(O)R¹⁰²;

-   -   (iv) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, and poly(lactic-co-glycolic acid) capped        with R¹⁰²,

wherein R¹¹¹ can be further substituted with R⁵ if valence permits, astable compound is formed, and the resulting compound ispharmaceutically acceptable;

R¹⁰² is

and

wherein all other variables are as defined herein.

In various different embodiments, —C₂-C₃₀ as used in the definition ofR¹¹¹ may be —C₂-C₂₈, —C₄-C₂₆, —C₄-C₂₄, —C₆-C₂₂, —C₆-C₂₀, —C₈-C₁₈,—C₈-C₁₆, —C₈-C₁₄, —C₈-C₁₂, —C₈-C₂₀, or —C₆-C₂₄

Non-limiting examples of Formula VIIIA include:

The disclosure also provides prostaglandin prodrugs of Formula IXA,Formula XA, Formula XIA, and Formula XIIA:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R³¹⁰ is alkyl or hydrogen;

L⁷ is selected from:

R²⁰⁸ and R²⁰⁹ are independently selected from: —C(O)R^(4b), —C(O)A,hydrogen, R²¹¹, and L⁸-R²¹²;

R^(4b) is selected from:

-   -   (i) —C₁₀-C₃₀alkylR⁵, —C₁₀-C₃₀alkenylR⁵, —C₁₀-C₃₀alkynylR⁵,        —C₁₀-C₃₀alkenylalkynylR⁵, —C₁₀-C₃₀alkyl, —C₁₀-C₃₀alkenyl,        —C₁₀-C₃₀alkynyl, —C₁₀-C₃₀alkenylalkynyl;    -   (ii) an unsaturated fatty acid residue including but not limited        to the carbon chains from linoleic acid        (—(CH₂)₈(CH)₂CH₂(CH)₂(CH₂)₄CH₃)), docosahexaenoic acid        (—(CH₂)₃(CHCHCH₂)₆CH₃)), eicosapentaenoic acid        (—(CH₂)₄(CHCHCH₂)₅CH₃)), alpha-linolenic acid        (—(CH₂)₈(CHCHCH₂)₃CH₃)) stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid or mead acid, and wherein, if        desired, each of which can be substituted with R⁵.

wherein either at least one of R²⁰⁸ and R²⁰⁹ is R²¹¹ or L⁸-R²¹²; or L⁷is selected from

L⁸ is —C(O)-alkyl-C(O)—, and —C(O)-alkenyl-C(O)—;

R²¹⁰ is

R²¹¹ is selected from:

polyethylene glycol, polypropylene glycol, polypropylene oxide,polylactic acid, a biodegradable polymer and poly(lactic-co-glycolicacid) each of which is optionally linked by a carbonyl and each iscapped with R²¹² including:

R²¹² is selected from:

and

wherein all other variables are defined herein.

In one embodiment R²¹² is

Carbonic Anhydrase Inhibitor Prodrugs

The disclosure provides carbonic anhydrase inhibitor prodrugs of FormulaIB, Formula IIB, Formula IIIB and Formula IVB:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R¹⁰ is selected from:

-   -   (i) N═C₄-C₃₀alkenylR⁵, —N═C₄-C₃₀alkynylR⁵,        —N═C₄-C₃₀alkenylalkynylR⁵, —N═C₁-C₃₀alkylR⁵, —N═C₄-C₃₀alkenyl,        —N═C₄-C₃₀alkynyl, —N═C₄-C₃₀alkenylalkynyl, —N═C₁-C₃₀alkyl,        —N═CH—C₃-C₃₀alkenylR⁵, —N═CH—C₃-C₃₀alkynylR⁵,        —N═CH—C₃-C₃₀alkenylalkynylR⁵, —N═C₁-C₃₀alkylR⁵,        —N═CH—C₃-C₃₀alkenyl, —N═CH—C₃-C₃₀alkynyl,        —N═CH—C₃-C₃₀alkenylalkynyl, —N═C₁-C₃₀alkyl, —NHC₃-C₃₀alkenylR⁵,        —NH—C₃-C₃₀alkynylR⁵, —NH—C₅-C₃₀alkenylalkynylR⁵,        —NHC₀-C₃₀alkylR⁵, —NHC₃-C₃₀alkenylR¹⁶, —NH—C₃-C₃₀alkynylR¹⁶,        —NH—C₅-C₃₀alkenylalkynylR¹⁶, —NHC₀-C₃₀alkylR¹⁶;    -   (ii) an imine-, amine- or amide-linked unsaturated fatty acid        residue including but not limited to derivatives of linoleic        acid (—N═CH(CH₂)₇(CH)₂CH₂(CH)₂(CH₂)₄CH₃,        —NHCH₂(CH₂)₇(CH)₂CH₂(CH)₂(CH₂)₄CH₃, or        —NHC(O)(CH₂)₇(CH)₂CH₂(CH)₂(CH₂)₄CH₃), docosahexaenoic acid        (—N═CH(CH₂)₂(CHCHCH₂)₆CH₃, —NH(CH₂)₃(CHCHCH₂)₆CH₃, or        —NHC(O)(CH₂)₂(CHCHCH₂)₆CH₃), eicosapentaenoic acid        (—N═CH(CH₂)₃(CHCHCH₂)₅CH₃, —NH(CH₂)₄(CHCHCH₂)₅CH₃, or        —NHC(O)(CH₂)₃(CHCHCH₂)₅CH₃), alpha-linolenic acid        (—N═CH(CH₂)₇(CHCHCH₂)₃CH₃, —NH(CH₂)₄(CHCHCH₂)₅CH₃, or        —NHC(O)(CH₂)₃(CHCHCH₂)₅CH₃), stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid or mead acid, each of which can        be further substituted with R⁵ (including for example a second        R⁵) if valence permits, a stable compound is formed, and the        resulting compound is pharmaceutically acceptable;    -   (iii) an imine-, amine- or amide-linked polypropylene glycol,        polypropylene oxide, polylactic acid, or poly(lactic-co-glycolic        acid) including:

or polyglycolic acid, or a polyester, polyamide, or other biodegradablepolymer, each of which can be capped to complete the terminal valence.In some embodiments, the compound can be capped with hydrogen, or can becapped to create a terminal ester or ether. For example, the moiety canbe capped with a terminal hydroxyl or carboxy which can be furtherderivatized to an ether or ester. And wherein each of which can befurther substituted with R⁵ if valence permits, a stable compound isformed, and the resulting compound is pharmaceutically acceptable; andwherein in some embodiments a terminal hydroxy or carboxy group can besubstituted to create an ether or ester, respectively;

-   -   (iv) —NHC(O)C₁₋₂₀alkyl, —NHC(O)C₁₋₂₀alkenyl,        —NHC(O)C₁₋₂₀alkynyl, —NHC(O)(C₁₋₂₀alkyl with at least one R⁵        substituent on the alkyl chain), —NHC(O)(C₁₋₂₀alkenyl with at        least one R⁵ substituent on the alkenyl chain)        —NHC(O)(C₁₋₂₀alkynyl with at least one R⁵ substituent on the        alkynyl chain), —NH(lactic acid)₂₋₂₀C(O)C₁₋₂₀alkyl, —NH(lactic        acid)₂₋₁₀C(O)C₁₋₂₀alkyl, —NH(lactic acid)₄₋₂₀C(O)C₁₋₂₀alkyl,        —NH(lactic acid)₂₋₂₀C(O)C₁₋₁₀alkyl, —NH(lactic        acid)₂₋₂₀C(O)C₄₋₁₀alkyl, —NH(lactic acid)₂₋₂₀C(O)OH, —NH(lactic        acid)₂₋₁₀C(O)OH, —NH(lactic acid)₄₋₂₀C(O)OH, —NH(lactic        acid)₂₋₁₀C(O)OH, —NH(lactic acid)₄₋₁₀C(O)OH,        —NH(lactide-co-glycolide)₂₋₁₀C(O)C₁₋₂₀alkyl,        —NH(lactide-co-glycolide)₄₋₁₀C(O)C₁₋₂₀alkyl,        —NH(lactide-co-glycolide)₂₋₁₀C(O)C₁₋₁₀alkyl,        —NH(lactide-co-glycolide)₂₋₁₀C(O)C₄₋₂₀alkyl, —NH(glycolic        acid)₂₋₁₀C(O)C₁₋₁₀alkyl, —NH(glycolic acid)₄₋₁₀C(O)C₁₋₁₀alkyl,        —NH(lactic acid)₄₋₁₀C(O)C₁₋₁₀alkyl, —NH(lactic        acid)₂₋₁₀C(O)C₁₋₁₀alkyl, NH(lactic acid)₂₋₁₀C(O)C₄₋₁₀alkyl,        —NH(lactic acid)₂₋₁₀C(O)C₄₋₁₀alkyl, or —NH(lactic        acid)₂₋₁₀OC(O)C₄₋₁₀alkyl;

and

-   -   (vi) NH₂ wherein R¹⁵ is R¹⁶;

R⁶²⁰ is selected at each instance from hydrogen, alkyl, alkenyl, alkynylcycloalkyl, cycloalkylalkyl, heterocyclyl, heterocycloalkyl, aryl,arylalkyl, heteroaryl, or heteroarylalkyl, each of which except hydrogenmay be optionally substituted with R⁵ if the resulting compound isstable and achieves the desired purpose and wherein the group cannot besubstituted with itself, for example alkyl would not be substituted withalkyl;

R⁶²² is hydrogen, hydroxy, amino, A, alkyl, alkoxy, alkenyl, alkynylcycloalkyl, cycloalkylalkyl, heterocyclyl, heterocycloalkyl, aryl,arylalkyl, heteroaryl, heteroarylalkyl, aryloxy, or stearoyl;

In one embodiment, —C₃-C₃₀ as used in the definition of R¹⁰ is —C₃-C₂₈,—C₃-C₂₆, —C₃-C₂₄, —C₃-C₂₂, —C₃-C₂₀, —C₃-C₁₈, —C₃-C₁₆, —C₃-C₁₄, —C₃-C₁₂,—C₅-C₁₂, —C₇-C₁₂, or —C₇-C₁₀.

In one embodiment R¹⁰ is selected from —N═CH—C₃-C₃₀alkenylR⁵,—N═CH—C₃-C₃₀alkynylR⁵, —N═CH—C₃-C₃₀alkenylalkynylR⁵, —N═C₁-C₃₀alkylR⁵,—N═CH—C₃-C₃₀alkenyl, —N═CH—C₃-C₃₀alkynyl, —N═CH—C₃-C₃₀alkenylalkynyl,

—N═C₁-C₃₀alkyl;

In one embodiment, R is selected from

and R¹⁵ is hydrogen.

In one embodiment of Formula IIB, R¹⁰ is

x is an integer selected from 1, 2, 3, 4, 5, 6, 7, or 8, and R¹⁵ ishydrogen. In a further embodiment, x is 2, 4, or 6.

In one embodiment of Formula IIB, R¹⁰ is selected from—NH(lactide-co-glycolide)₂₋₁₀C(O)C₁₋₂₀alkyl,—NH(lactide-co-glycolide)₄₋₁₀C(O)C₁₋₂₀alkyl,—NH(lactide-co-glycolide)₂₋₁₀C(O)C₁₋₁₀alkyl, and—NH(lactide-co-glycolide)₂₋₁₀C(O)C₄₋₂₀alkyl and R¹⁵ is hydrogen.

Non-limiting examples of R¹⁰ include:

wherein all other variables are as defined herein.

Non-limiting Examples of Formula IIB include

In one embodiment, the compound of Formula IIB is

The disclosure provides carbonic anhydrase inhibitor prodrugs of FormulaVB, Formula VIB, and Formula VIIB:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R¹¹⁸ is selected from:

-   -   (i) —C(O)C₅-C₃₀alkylR⁵, —C(O)C₂-C₃₀alkenylR⁵,        —C(O)C₂-C₃₀alkynylR⁵, —C(O)C₄-C₃₀alkenylalkynylR⁵,        —C(O)C₅-C₃₀alkyl, —C(O)C₂-C₃₀alkenyl, —C(O)C₂-C₃₀alkynyl, and        —C(O)C₄-C₃₀alkenylalkynyl;    -   (ii) —C(O)(C₁₋₃₀alkyl with at least one R⁵ substituent on the        alkyl chain), —C(O)(C₁₋₃₀alkenyl with at least one R⁵        substituent on the alkenyl chain), —C(O)(C₁₋₃₀alkynyl with at        least one R⁵ substituent on the alkynyl chain), -(lactic        acid)₁₋₂₀C(O)C₁₋₃₀alkyl, -(lactic acid)₁₋₁₀C(O)C₁₋₃₀alkyl,        -(lactic acid)₄₋₂₀C(O)C₁₋₃₀alkyl, -(lactic        acid)₁₋₂₀C(O)C₁₋₁₀alkyl, -(lactic acid)₁₋₂₀C(O)C₄₋₁₀alkyl,        -(lactic acid)₁₋₂₀C(O)OH, -(lactic acid)₁₋₁₀C(O)OH, -(lactic        acid)₄₋₂₀C(O)OH, -(lactic acid)₁₋₁₀C(O)OH, -(lactic        acid)₄₋₁₀C(O)OH, -(lactide-co-glycolide)₁₋₁₀C(O)C₁₋₃₀alkyl,        -(lactide-co-glycolide)₄₋₁₀C(O)C₁₋₃₀alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)C₁₋₁₂alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)C₄₋₂₂alkyl, -(glycolic        acid)₁₋₁₀C(O)C₁₋₁₀alkyl, -(glycolic acid)₄₋₁₀C(O)C₁₋₁₀alkyl,        -(lactic acid)₄₋₁₀C(O)C₁₋₁₀alkyl, -(lactic        acid)₁₋₁₀C(O)C₁₋₁₀alkyl, -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl,        -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl, and -(lactic        acid)₁₋₁₀C(O)C₄₋₁₀alkyl;    -   (iii) an unsaturated fatty acid residue including but not        limited to the carbonyl fragment taken from linoleic acid        (—(CH₂)₈(CH)₂CH₂(CH)₂(CH₂)₄CH₃)), docosahexaenoic acid        (—(CH₂)₃(CHCHCH₂)₆CH₃)), eicosapentaenoic acid        (—(CH₂)₄(CHCHCH₂)₅CH₃)), alpha-linolenic acid        (—(CH₂)₈(CHCHCH₂)₃CH₃)), stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid and mead acid, each of which can        be further optionally further substituted with R⁵ (including for        example a second R⁵) if valence permits, a stable compound is        formed, and the resulting compound is pharmaceutically        acceptable;    -   (iv) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, poly(lactic-co-glycolic acid),        polyglycolic acid, polyester, polyamide, and other biodegradable        polymers, each of which can be capped to complete the terminal        valence or to create a terminal ether or ester;

-   -   (vi) —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl, (C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₂₋₁₀(C(O)CH(CH₃)O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₂alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₂₂alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₂₋₁₀(C(O)CH₂O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₂alkyl, and        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₄₋₂₂alkyl; and

wherein all other variables are as defined herein.

In various different embodiments, —C₁₀-C₃₀ as used in the definition ofR¹¹⁸ is —C₁₀-C₁₈, —C₁₀-C₁₆, —C₁₀-C₁₄, —C₁₀-C₁₂, —C₁₉-C₂₈, —C₁₉-C₂₆,—C₁₉-C₂₄, —C₁₉-C₂₂, —C₁₉-C₂₀, —C₂₀- C₂₈, —C₂₀-C₂₆, —C₂₀-C₂₄, —C₂₀-C₂₂,—C₂₂-C₂₈, —C₂₂-C₂₆, —C₂₂-C₂₄, or —C₂₆-C₂₈.

Non-limiting examples of Formula VB include:

Compounds of Formula VIIB are drawn as

where the bond between the aromatic ring and the imidazole ring is drawnas a wavy line. In one embodiment, compounds of Formula VIIB are the Zisomer. In one embodiment, compounds of Formula VIIB are the E isomer.For example, in one embodiment,

is the Z isomer:

andin an alternative embodiment, is the E isomer:

The disclosure provides carbonic anhydrase inhibitor prodrugs of FormulaVIIIB and Formula IXB:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

wherein R³²³ is independently selected from polyethylene glycol,polypropylene glycol, polypropylene oxide, polylactic acid,poly(lactic-co-glycolic acid), polyglycolic acid, polyester, polyamide,

In certain embodiments of Formula VIIIB or Formula IXB, R³²³ is

and R^(31a) is —C(O)alkyl.

In certain embodiments of Formula VIIIB or Formula IXB, R³²³ is

and R^(31a) is —C(O)alkyl.

In certain embodiments of Formula VIIIB or Formula IXB, R³²³ is

and R^(31a) is —C(O)alkyl.

Non-limiting Examples of Formula VIIIB include

Compounds of Formula VIIIB are drawn as

where the bond between the aromatic ring and the imidazole ring is drawnas a wavy line. In one embodiment, compounds of Formula VIIIB are the Zisomer. In one embodiment, compounds of Formula VIIIB are the E isomer.

The disclosure provides carbonic anhydrase inhibitor prodrugs of FormulaXB, Formula XIB, Formula XIIB, Formula XIIIB, Formula XIVB, and FormulaXVB:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R¹¹⁹ is selected from: acyl, R¹²⁰, polyethylene glycol, polypropyleneglycol, polypropylene oxide, polylactic acid, poly(lactic-co-glycolicacid), a polyglycolic acid, a polyester, polyamide, or otherbiodegradable polymer, wherein each R¹¹⁹ other than R¹²⁰ is substitutedwith at least one L⁴-R¹²¹;

R¹²⁰ is selected from:

R¹²¹ is selected from:

Q is selected from: N, CH, and CR²³;

R²³, R²⁴, and R²⁵ are independently selected from: hydrogen, halogen,hydroxyl, cyano, mercapto, nitro, amino, aryl, alkyl, alkoxy, alkenyl,alkynyl cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocycloalkyl,aryl, arylalkyl, heteroaryl, heteroarylalkyl, aryloxy, —S(O)₂alkyl,—S(O)alkyl, —P(O)(Oalkyl)₂, B(OH)₂, —Si(CH₃)₃, —COOH, —COOalkyl, —CONH₂,

each of which except halogen, nitro, and cyano, may be optionallysubstituted, for example with halogen, alkyl, aryl, heterocycle orheteroaryl.

R²⁶ is selected from H, C(O)A, —C₀-C₁₀alkylR⁵, —C₂-C₁₀alkenylR⁵,—C₂-C₁₀alkynylR⁵, —C₂-C₁₀alkenyl, and —C₂-C₁₀alkynyl.

R¹⁴¹ is selected from hydrogen, —C(O)NR¹⁶¹R¹⁶², —C(O)R¹⁶¹, —C(O)OR¹⁶¹,nitro, amino, —NR¹³⁴R¹³⁵, alkyl, alkoxy, alkylalkoxy, alkoxyalkoxy,haloalkoxy, cycloalkyl, heterocycloalkyl, heteroaryl, aryl, and halogen;

R¹³⁴ and R¹³⁵ are independently selected from H, alkyl, —SO₂CH₃,—C(O)CH₃, and —C(O)NH₂;

R¹⁶¹ and R¹⁶² are independently selected from hydrogen, aryl, alkyl,cycloalkyl, arylalkyl, heteroaryl, heteroarylalkyl, and heterocyclyl;

R³⁰¹ is selected from hydrogen, —C(O)NR¹⁶¹R¹⁶², —C(O)R¹⁶¹, —C(O)OR¹⁶¹,nitro, amino, —NR¹³⁴R¹³⁵, alkyl, alkoxy, alkylalkoxy, alkoxyalkoxy,haloalkoxy, cycloalkyl, heterocycloalkyl, heteroaryl, aryl, halogen,—O(CH₂)₂NR¹³⁴R¹³⁵, and —N(CH₃)(CH₂)₂NR¹³⁴R¹³⁵;

or R¹³⁴ and R¹³⁵ can together form a heterocycloalkyl;

R¹⁸⁰ is C₁-C₆ alkyl, acyl, or hydrogen;

R¹⁹¹ is selected from:

and R¹⁹⁵;

t is independently selected from 0, 1, 2, 3, and 4;

R¹⁹² is independently selected from alkyl, cycloalkyl, aryl, heteroaryl,heterocycle, cyano, amino, hydroxyl, and acyl, each of which R¹⁹² isoptionally substituted with a R¹⁷⁵ group;

R¹⁹³ is independently selected from alkyl, cycloalkyl, aryl, heteroaryl,heterocycle, amino, hydroxyl, and acyl;

or two R¹⁹³ groups with the carbon to which they are linked form acarbonyl group;

or two R¹⁹³ groups with the carbon(s) to which they are linked form afused or spirocyclic ring;

R¹⁹⁴ is selected from alkyl, cycloalkyl, R¹⁷⁵, and acyl; and

R¹⁹⁵ is selected from aryl, heteroaryl, cycloalkyl, and heterocycle,wherein each R¹⁹⁵ is optionally substituted with 1, 2, 3, or 4 R¹⁹²groups;

R¹⁷⁵ is selected from: C(O)A, C(O)R⁴, and R¹⁷⁸;

R¹⁷⁸ is selected from:

-   -   (i) carbonyl linked polyethylene glycol, carbonyl linked        polypropylene glycol, carbonyl linked polypropylene oxide,        polylactic acid, poly(lactic-co-glycolic acid), polyglycolic        acid, polyester, polyamide,

and other biodegradable polymers, wherein each R¹⁷⁸ is optionallysubstituted with R^(31a) or R³¹¹, and wherein each of R¹⁷⁸ with aterminal hydroxy or carboxy group can be substituted to create an etheror ester;

-   -   (ii) -(lactic acid)₁₋₂₀C(O)C₁₋₂₂alkyl, -(lactic        acid)₁₋₁₀C(O)C₁₋₂₂alkyl, -(lactic acid)₄₋₂₀C(O)C₁₋₂₂alkyl,        -(lactic acid)₁₋₂₀C(O)C₁₋₁₀alkyl, -(lactic        acid)₁₋₂₀C(O)_(C4-10)alkyl, -(lactic acid)₁₋₂₀C(O)OH, -(lactic        acid)₁₋₁₀C(O)OH, -(lactic acid)₄₋₂₀C(O)OH, -(lactic        acid)₁₋₁₀C(O)OH, -(lactic acid)₄₋₁₀C(O)OH,        -(lactide-co-glycolide)₁₋₁₀C(O)C₁₋₂₂alkyl,        -(lactide-co-glycolide)₄₋₁₀C(O)C₁₋₂₂alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)C₁₋₁₂alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)C₄₋₂₂alkyl, -(glycolic        acid)₁₋₁₀C(O)C₁₋₁₀alkyl, -(glycolic acid)₄₋₁₀C(O)C₁₋₁₀alkyl,        -(lactic acid)₄₋₁₀C(O)C₁₋₁₀alkyl, -(lactic        acid)₁₋₁₀C(O)C₁₋₁₀alkyl, -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl,        -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl, or -(lactic        acid)₁₋₁₀C(O)C₄₋₁₀alkyl;    -   (iii) —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl, (C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₂₋₁₀(C(O)CH(CH₃)O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₂alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₂₂alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₂₋₁₀(C(O)CH₂O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₂alkyl, and        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₄₋₂₂alkyl;

R⁶¹⁵ and R⁶¹⁶ are independently selected from: —C(O)R⁶¹⁸, C(O)A, andhydrogen, each of which except hydrogen can be optionally substitutedwith R⁵;

R⁶¹⁷ is selected from:

-   -   (i) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, and poly(lactic-co-glycolic acid),        polyglycolic acid, or a polyester, a polyamide, or other        biodegradable polymers, wherein a terminal hydroxy or carboxy        group can be substituted to create an ether or ester,        respectively;    -   (ii) —C₁₀-C₃₀alkylR⁵, —C₁₀-C₃₀alkenylR⁵, —C₁₀-C₃₀alkynylR⁵,        —C₁₀-C₃₀alkenylalkynylR⁵, —C₁₀-C₃₀alkyl, —C₁₀-C₃₀alkenyl,        —C₁₀-C₃₀alkynyl, —C₁₀-C₃₀alkenylalkynyl;    -   (iii) an unsaturated fatty acid residue including but not        limited the carbon fragment taken from linoleic acid        (—(CH₂)₈(CH)₂CH₂(CH)₂(CH₂)₄CH₃)), docosahexaenoic acid        (—(CH₂)₃(CHCHCH₂)₆CH₃)), eicosapentaenoic acid        (—(CH₂)₄(CHCHCH₂)₅CH₃)), alpha-linolenic acid        (—(CH₂)₈(CHCHCH₂)₃CH₃)) stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid or mead acid; and    -   (iv) alkyl, cycloalkyl, cycloalkylalkyl, heterocycle,        heterocycloalkyl, arylalkyl, heteroarylalkyl;

R⁶¹⁸ is selected from:

-   -   (iii) —C₁₀-C₃₀alkylR⁵, —C₁₀-C₃₀alkenylR⁵, —C₁₀-C₃₀alkynylR⁵,        —C₁₀-C₃₀alkenylalkynylR⁵, —C₁₀-C₃₀alkyl, —C₁₀-C₃₀alkenyl,        —C₁₀-C₃₀alkynyl, —C₁₀-C₃₀alkenylalkynyl; and    -   (iv) an unsaturated fatty acid residue including but not limited        to the carbon chains from linoleic acid        (—(CH₂)₈(CH)₂CH₂(CH)₂(CH₂)₄CH₃)), docosahexaenoic acid        (—(CH₂)₃(CHCHCH₂)₆CH₃)), eicosapentaenoic acid        (—(CH₂)₄(CHCHCH₂)₅CH₃)), alpha-linolenic acid        (—(CH₂)₈(CHCHCH₂)₃CH₃)), stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid and mead acid,        -   and wherein, if desired, each of which can be substituted            with R⁵;

R⁶³⁶ is selected from C(O)A,

R⁶³⁷ is selected from hydrogen, —C(O)A, —C(O)alkyl, aryl, alkyl,cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocycloalkyl, arylalkyl,heteroaryl, and heteroarylalkyl; and

L³³ is selected from: bond, —OC₁-C₃₀alkyl-O—, —NHC₁-C₃₀alkyl-O—,N(alkyl)C₁-C₃₀alkyl-O—, —NHC₁-C₃₀alkyl-NH—, N(alkyl)C₁-C₃₀alkyl-NH—,—NHC₁-C₃₀alkyl-N(alkyl)-, —N(alkyl)C₁-C₃₀alkyl-N-(alkyl)-,—OC₁-C₃₀alkenyl-O—, —NHC₁-C₃₀alkenyl-O—, N(alkyl)C₁-C₃₀alkenyl-O—,—NHC₁-C₃₀alkenyl-NH—, N(alkyl)C₁-C₃₀alkenyl-NH—,—NHC₁-C₃₀alkenyl-N(alkyl)-, —N(alkyl)C₁-C₃₀alkenyl-N-(alkyl)-,—OC₁-C₃₀alkynyl-O—, —NHC₁-C₃₀alkynyl-O—, N(alkyl)C₁-C₃₀alkynyl-O—,—NHC₁-C₃₀alkynyl-NH—, N(alkyl)C₁-C₃₀alkynyl-NH—,—NHC₁-C₃₀alkynyl-N(alkyl)-, and —N(alkyl)C₁-C₃₀alkynyl-N-(alkyl)-; and

wherein all other variables are as defined herein.

The disclosure provides carbonic anhydrase inhibitor prodrugs of FormulaXVIB, Formula XVIIB, and Formula XVIIIB:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R¹¹⁶ is selected from: R¹¹⁷, alkyl, alkyloxy, acyl, polyethylene glycol,polypropylene glycol, polypropylene oxide, polylactic acid,poly(lactic-co-glycolic acid), a polyglycolic acid, a polyester,polyamide, or other biodegradable polymer, wherein each R¹¹⁶ other thanR¹¹⁷ is substituted with at least one L⁴-R¹²¹;

wherein R¹¹⁶ can be further substituted with R⁵ if valence permits, astable compound is formed, and the resulting compound ispharmaceutically acceptable.

R¹¹⁷ is selected from:

and

wherein all other variables are as defined herein.

The disclosure provides carbonic anhydrase inhibitor prodrugs of FormulaXIXB:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R^(341a) and R^(341b) are independently selected from hydrogen andalkyl.

In one embodiment of Formula XIXB, R^(341a) and R^(341b) are hydrogen.

In one embodiment of Formula XIXB, R^(341a) is hydrogen and R^(341b) ismethyl.

In one embodiment of Formula XIXB, R^(341a) is methyl and R^(341b) ishydrogen.

In one embodiment of Formula XIXB is the malic salt.

In one embodiment of Formula XIXB is the maleate salt.

Sunitinib Prodrugs

The disclosure provides Sunitinib prodrugs of Formula IC and FormulaIIC:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof. This structure is related to Sunitinib (marketed inthe form of the (−)-malic acid salt as SUTENT® by Pfizer, and previouslyknown as SU11248), which is an oral, small-molecule, multi-targetedreceptor tyrosine kinase (RTK) inhibitor that was approved by the FDAfor the treatment of renal cell carcinoma (RCC) and imatinib-resistantgastrointestinal stromal tumor (GIST) on Jan. 26, 2006. Sunitinib wasthe first cancer drug simultaneously approved for two differentindications. Sunitinib inhibits cellular signaling by targeting multiplereceptor tyrosine kinases (RTKs). These include all receptors forplatelet-derived growth factor (PDGF-Rs) and vascular endothelial growthfactor receptors (VEGFRs), which play a role in both tumor angiogenesisand tumor cell proliferation. The simultaneous inhibition of thesetargets leads to both reduced tumor vascularization and cancer celldeath, and, ultimately, tumor shrinkage. Sunitinib and derivativesthereof are described in U.S. Pat. Nos. 7,211,600; 6,573,293; and7,125,905.

R³⁰ is selected from:

-   -   (i) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, poly(lactic-co-glycolic acid), a        polyglycolic acid, a polyester, and a polyamide

wherein R³⁰ is optionally substituted with R³¹,

-   -   and wherein each R³⁰ with a terminal hydroxy or carboxy group        can be substituted to create an ether or ester, respectively;

and

wherein all other variables are defined herein.

The disclosure provides Sunitinib prodrugs of Formula IIIC:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

L¹⁰ is —O—, —NH—, or —N(alkyl)-;

R³¹⁴ is an unsaturated fatty acid residue including but not limited tothe carbon chains from linoleic acid (—(CH₂)₈(CH)₂CH₂(CH)₂(CH₂)₄CH₃)),docosahexaenoic acid (—(CH₂)₃(CHCHCH₂)₆CH₃)), eicosapentaenoic acid(—(CH₂)₄(CHCHCH₂)₅CH₃)), alphalinolenic acid (—(CH₂)₈(CHCHCH₂)₃CH₃)),stearidonic acid, y-linolenic acid, arachidonic acid, docosatetraenoicacid, palmitoleic acid, vaccenic acid, paullinic acid, oleic acid,elaidic acid, gondoic acid, euric acid, nervonic acid and mead acid, andwherein, if desired, each of which can be substituted with R⁵; and

R⁵ is defined above.

In one embodiment, R³¹⁴ is

The disclosure provides Sunitinib prodrugs of Formula IVC:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R¹²¹ is as defined herein.

The disclosure provides Sunitinib prodrugs of Formula VIC:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R³² is selected from: R³⁵, R¹²¹, alkyl, alkyloxy, polyethylene glycol,polypropylene glycol, polypropylene oxide, polylactic acid,poly(lactic-co-glycolic acid), a polyglycolic acid, a polyester,polyamide, or other biodegradable polymer, wherein each R³² other thanR³⁵ and R¹²¹ is substituted with at least one L⁴-R¹²¹;

wherein R³² can be further substituted with R⁵ if valence permits, astable compound is formed, and the resulting compound ispharmaceutically acceptable.

R³⁵ is selected from:

wherein all other variables are as defined herein.

In one embodiment, R³⁵ is selected from

and R^(121 is)

and R¹⁵ is hydrogen.

In a further embodiment, x and y are independently selected from 1, 2,3, 4, 5, and 6.

In one embodiment, R³⁵ is

R¹²¹ is

and R¹⁵ is hydrogen.

Non-limiting examples of Formula VC include

The disclosure provides Sunitinib prodrugs of Formula VIC:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

L⁶ is selected from —O—, —NH—, —N(alkyl)₁₋₄-, —C(O)O—, —S—, —C(O)— and—OC(O)—;

R³⁷ is selected from: R¹²¹, polyethylene glycol, polypropylene glycol,polypropylene oxide, polylactic acid, poly(lactic-co-glycolic acid), apolyglycolic acid, a polyester, a polyamide, or other biodegradablepolymer, wherein each R³⁷ other than R³⁸ and R¹²¹ is substituted with atleast one L⁶-R¹²¹;

R³⁸ is selected from:

and

wherein all other variables are as defined herein.

Timolol Prodrugs

The disclosure provides Timolol prodrugs of Formula ID:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R³³ is selected from:

-   -   (i) carbonyl linked polyethylene glycol, carbonyl linked        polypropylene glycol, carbonyl linked polypropylene oxide,        polylactic acid, poly(lactic-co-glycolic acid), a polyglycolic        acid, a polyester, and a polyamide;

or other biodegradable polymer, wherein each R³³ is optionallysubstituted with R^(31a) or R³¹¹, and wherein each of R³³ with aterminal hydroxy or carboxy group can be substituted to create an etheror ester, respectively; and

-   -   (iii) —C(O)C₁₇₋₃₀alkyl, —C(O)C₁₀₋₃₀alkenyl, —C(O)C₁₀₋₃₀alkynyl,        —C(O)(C₁₀₋₃₀alkyl with at least one R⁵ substituent on the alkyl        chain), —C(O)(C₁₀₋₃₀alkenyl, with at least one R⁵ substituent on        the alkenyl chain), and —C(O)(C₁₀₋₃₀alkynyl, with at least one        R⁵ substituent on the alkynyl chain);    -   (iv) -(lactic acid)₁₋₂₀C(O)C₁₋₃₀alkyl, -(lactic        acid)₁₋₁₀C(O)C₁₋₃₀alkyl, -(lactic acid)₄₋₂₀C(O)C₁₋₃₀alkyl,        -(lactic acid)₁₋₂₀C(O)C₁₋₁₀alkyl, -(lactic        acid)₁₋₂₀C(O)C₄₋₁₀alkyl, -(lactic acid)₁₋₂₀C(O)OH, -(lactic        acid)₁₋₁₀C(O)OH, -(lactic acid)₄₋₂₀C(O)OH, -(lactic        acid)₁₋₁₀C(O)OH, -(lactic acid)₄₋₁₀C(O)OH,        -(lactide-co-glycolide)₁₋₁₀C(O)C₁₋₂₂alkyl,        -(lactide-co-glycolide)₄₋₁₀C(O)C₁₋₂₂alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)C₁₋₁₂alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)C₄₋₂₂alkyl, -(glycolic        acid)₁₋₁₀C(O)C₁₋₁₀alkyl, -(glycolic acid)₄₋₁₀C(O)C₁₋₁₀alkyl,        -(lactic acid)₄₋₁₀C(O)C₁₋₁₀alkyl, -(lactic        acid)₁₋₁₀C(O)C₁₋₁₀alkyl, -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl,        -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl, or -(lactic        acid)₁₋₁₀C(O)C₄₋₁₀alkyl;    -   (v) —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl, (C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₂₋₁₀(C(O)CH(CH₃)O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₂alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₂₂alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₂₋₁₀(C(O)CH₂O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₂alkyl, and        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₄₋₂₂alkyl;

R⁴³³ is selected from hydrogen, —C(O)A, acyl, aryl, alkyl, alkenyl,alkynyl cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocycloalkyl,aryl, arylalkyl, heteroaryl, and heteroarylalkyl; and

wherein all other variables are as defined herein.

In one embodiment R³¹ is —C(O)A, alkyl, or PEG.

In one embodiment R³¹ is —C(O)A, wherein A is methyl.

In one embodiment R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is —C(O)(CH₂)₁₆CH₃ and R⁴³³ is hydrogen.

In one embodiment, R⁴³³ is hydrogen and R³³ is

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

and R⁴³³ is hydrogen.

In one embodiment, R³³ is

R⁴³³ is hydrogen, x is selected from 1, 2, 3, 4, 5, and 6, and R³¹ is—C(O)Me.

In one embodiment, a compound of Formula ID is the pharmaceuticallyacceptable HCl salt.

In one embodiment, a compound of Formula ID is the pharmaceuticallyacceptable maleic salt.

Non-limiting Examples of ID include

The disclosure provides Timolol prodrugs of Formula IID:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R¹²³ is selected from:

-   -   (ii) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, poly(lactic-co-glycolic acid),        polyglycolic acid, polyester, polyamide,

-   -   -   wherein each R¹²³ is optionally substituted with R³¹¹ or            R^(31a), and wherein each of R¹²³ with a terminal hydroxy or            carboxy group can be substituted to create an ether or            ester;

    -   (ii) —C(O)C₁₇₋₃₀alkyl, —C(O)C₁₀₋₃₀alkenyl, —C(O)C₁₀₋₃₀alkynyl,        —C(O)(C₁₀₋₃₀alkyl with at least one R⁵ substituent on the alkyl        chain), —C(O)(C₁₀₋₃₀alkenyl, with at least one R⁵ substituent on        the alkenyl chain) —C(O)(C₁₀₋₃₀alkynyl, with at least one R⁵        substituent on the alkynyl chain), -(lactic        acid)₁₋₂₀C(O)C₁₋₃₀alkyl, -(lactic acid)₁₋₁₀C(O)C₁₋₃₀alkyl,        -(lactic acid)₄₋₂₀C(O)C₁₋₃alkyl, -(lactic        acid)₁₋₂₀C(O)C₁₋₁₀alkyl, -(lactic acid)₁₋₂₀C(O)C₄₋₁₀alkyl,        -(lactic acid)₁₋₂₀C(O)OH, -(lactic acid)₁₋₁₀C(O)OH, -(lactic        acid)₄₋₂₀C(O)OH, -(lactic acid)₁₋₁₀C(O)OH, -(lactic        acid)₄₋₁₀C(O)OH, -(lactide-co-glycolide)₁₋₁₀C(O)C₁₋₂₂alkyl,        -(lactide-co-glycolide)₄₋₁₀C(O)C₁₋₂₂alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)C₁₋₁₂alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)C₄₋₂₂alkyl, -(glycolic        acid)₁₋₁₀C(O)C₁₋₁₀alkyl, -(glycolic acid)₄₋₁₀C(O)C₁₋₁₀alkyl,        -(lactic acid)₄₋₁₀C(O)C₁₋₁₀alkyl, -(lactic        acid)₁₋₁₀C(O)C₁₋₁₀alkyl, -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl,        -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl, or -(lactic        acid)₁₋₁₀C(O)C₄₋₁₀alkyl;

    -   (iii) —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl, (C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₂₋₁₀(C(O)CH(CH₃)O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₂alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₂₂alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₂₋₁₀(C(O)CH₂O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₂alkyl, and        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₄₋₂₂alkyl;

    -   (iv) hydrogen, —C(O)A, aryl, alkyl, alkenyl, alkynyl cycloalkyl,        cycloalkylalkyl, heterocyclyl, heterocycloalkyl, aryl,        arylalkyl, heteroaryl, and heteroarylalkyl;

R¹⁰⁶ is selected from:

-   -   —C(O)C₁₀₋₃₀alkyl, —C(O)C₁₀₋₃₀alkenyl, —C(O)C₁₀₋₃₀alkynyl,        —C(O)(C₁₀₋₃₀alkyl with at least one R⁵ substituent on the alkyl        chain), —C(O)(C₁₀₋₃₀alkenyl, with at least one R⁵ substituent on        the alkenyl chain) —C(O)(C₁₀₋₃₀alkynyl, with at least one R⁵        substituent on the alkynyl chain), -(lactic        acid)₁₋₂₀C(O)C₁₋₃₀alkyl, -(lactic acid)₁₋₁₀C(O)C₁₋₃₀alkyl,        -(lactic acid)₄₋₂₀C(O)C₁₋₃₀alkyl, -(lactic        acid)₁₋₂₀C(O)C₁₋₁₀alkyl, -(lactic acid)₁₋₂₀C(O)_(C4-10)alkyl,        -(lactic acid)₁₋₂₀C(O)OH, -(lactic acid)₁₋₁₀C(O)OH, -(lactic        acid)₄₋₂₀C(O)OH, -(lactic acid)₁₋₁₀C(O)OH, -(lactic        acid)₄₋₁₀C(O)OH, -(lactide-co-glycolide)₁₋₁₀C(O)_(C1-22)alkyl,        -(lactide-co-glycolide)₄₋₁₀C(O)_(C1-22)alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)_(C1-12)alkyl,        -(lactide-co-glycolide)₁₋₁₀C(O)_(C4-22)alkyl, -(glycolic        acid)₁₋₁₀C(O)_(C1-10)alkyl, -(glycolic        acid)₄₋₁₀C(O)_(C1-10)alkyl, -(lactic acid)₄₋₁₀C(O)C₁₋₁₀alkyl,        -(lactic acid)₁₋₁₀C(O)C₁₋₁₀alkyl, -(lactic        acid)₁₋₁₀C(O)C₄₋₁₀alkyl, -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl, and        -(lactic acid)₁₋₁₀C(O)C₄₋₁₀alkyl;    -   (iii) —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₄₋₂₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₂₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₄₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl, (C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₁₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₂₋₁₀(C(O)CH(CH₃)O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₁₋₁₂alkyl,        —(C(O)CH₂O)₁₋₁₀(C(O)CH(CH₃)O)₁₋₁₀C(O)C₄₋₂₂alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₂₋₁₀(C(O)CH₂O)₂₋₁₀C(O)C₁₋₃₀alkyl,        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₁₋₁₂alkyl, and        —(C(O)CH(CH₃)O)₁₋₁₀(C(O)CH₂O)₁₋₁₀C(O)C₄₋₂₂alkyl;

x′ and y′ are independently selected from any integer between 1 and 30(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,21, 22, 23, 24, 25, 26, 27, 28, 29 or 30). In one embodiment x′ and y′are independently selected from the following ranges: 1 to 5, 6 to 11,12 to 17, 18 to 23, and 24 to 30 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28,29 or 30). In a preferred embodiment, x and y are independently selectedfrom any integer between 1 and 10 (1, 2, 3, 4, 5, 6, 7, 8, 9, or 10);and wherein all other integers are as defined herein.

In one embodiment, R¹⁰⁶ is —C(O)(CH₂)₁₆CH₃ and R¹²³ is hydrogen.

In one embodiment, R¹²³ is hydrogen and R¹⁰⁶ is

In one embodiment, R¹²³ is

In one embodiment, R¹²³ is

In one embodiment, R¹²³ is

In one embodiment, R¹⁰⁶ is

x is 1, and R¹²³ is —C(O)A.

In one embodiment, R¹⁰⁶ is

and R^(31a) is —C(O)alkyl.

In one embodiment, R¹⁰⁶ is

and R^(31a) is —C(O)alkyl wherein alkyl is methyl.

In one embodiment R¹²³ is selected from

In one embodiment R^(31a) is selected from —C(O)alkyl, stearoyl, and

Non-limiting Examples of Formula IID include

The disclosure provides Timolol prodrugs of Formula IIID and FormulaIVD:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R³⁴ is selected from: R³⁸¹, carbonyl linked polyethylene glycol,carbonyl linked polypropylene glycol, carbonyl linked polypropyleneoxide, polylactic acid, and poly(lactic-co-glycolic acid), apolyglycolic acid, a polyester, polyamide,

or other biodegradable polymer, wherein each R³⁴ other than R³⁸¹ issubstituted with at least one L⁴-R¹²¹;

R^(31b) is hydrogen, aryl, alkyl, cycloalky, cycloalkyl,cycloalkylalkyl, heterocyclyl, heterocycloalkyl, arylalkyl, heteroaryl,heteroarylalkyl, and polyethylene glycol;

R³⁸¹ is selected from:

and

wherein all other variables are as defined herein.

The disclosure provides Timolol prodrugs of Formula VD and Formula VID:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R³⁶⁴ is selected from: acyl, carbonyl linked polyethylene glycol,carbonyl linked polypropylene glycol, carbonyl linked polypropyleneoxide, polylactic acid, poly(lactic-co-glycolic acid), polyglycolicacid, polyester, polyamide,

R³⁶⁰ is selected from

and

wherein all other variables are as defined herein.

In one embodiment, R³⁶⁴ is

and R^(31a) is —C(O)alkyl.

In one embodiment, R³⁶⁴ is

and R^(31a) is —C(O)Me.

In one embodiment, R³⁶⁴ is

R^(31a) is —C(O)Me, and x′ is an integer between 1 and 6 (1, 2, 3, 4, 5,or 6);

In one embodiment, R³⁶⁴ is

and R^(31a) is stearoyl;

In one embodiment, R³⁶⁴ is

x′ is an integer between 1 and 6 (1, 2, 3, 4, 5, or 6), and y is 11 or17, or in an alternative embodiment, y is 10 or 16.

In one embodiment, R³⁶⁰ is

R¹²¹ is

and R¹⁵ is hydrogen.

In one embodiment, R³⁶⁰ is

R¹²¹ is

and R¹⁵ is hydrogen.

In one embodiment, R³⁶⁰ is

R¹²¹ is

In one embodiment, R³⁶⁰ is

and R¹²¹ is

In certain embodiments, R³⁶⁰ is

x and y are independently selected from 1, 2, 3, 4, 5, and 6, and z is1, 2, or 3.

In certain embodiments, R³⁶⁰ is

x and y are independently selected from 1, 2, and 3, and z is 1, 2, or3.

In certain embodiments, R³⁶⁰ is

x and y are independently selected from 1, 2, and 3, z is 1, 2, or 3,and R³⁶⁴ is

In certain embodiments, x′ and x are 1 and y and y′ are independentlyselected from 1, 2, 3, 4, 5, and 6.

In certain embodiments, x′ and x are 2 and y and y′ are independentlyselected from 1, 2, 3, 4, 5, and 6.

In certain embodiments, x′ and x are 3 and y and y′ are independentlyselected from 1, 2, 3, 4, 5, and 6.

In certain embodiments, x′ and x are 1 and y and y′ are independentlyselected from 1, 2, or 3.

In certain embodiments, x′ and x are 2 and y and y′ are independentlyselected from 1, 2, or 3.

In certain embodiments, y′ and y are 1 and x and x′ are independentlyselected from 1, 2, 3, 4, 5, and 6.

In certain embodiments, y′ and y are 2 and x and x′ are independentlyselected from 1, 2, 3, 4, 5, and 6.

In certain embodiments, y′ and y are 3 and x and x′ are independentlyselected from 1, 2, 3, 4, 5, and 6.

In certain embodiments, y′ and y are 1 and x and x′ are independentlyselected from 1, 2, and 3.

In certain embodiments, y′ and y are 2 and x and x′ are independentlyselected from 1, 2, and 3.

Non-limiting examples of compounds of Formula VD include

Non-limiting Examples of Compound of Formula VID include:

The disclosure provides Timolol prodrugs of Formula VIID:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof

wherein

R³⁶⁶ is selected from

R³¹⁶ is selected from

wherein all other variables are as defined herein.

Non-limiting examples of R⁶¹⁷ include:

In one embodiment, R³⁶⁰ is

and R³⁶⁶ is

In one embodiment, R³⁶⁰ is

and R³⁶⁶ is

In one embodiment, R³⁶⁰ is

x is 1, 2, 3, or 4, and z is 1, 2, 3, or 4.

In one embodiment, R³⁶⁶ is

x′ an integer between 0 and 4 (0, 1, 2, 3, or 4), and z is an integerbetween 1 and 4 (1, 2, 3, or 4).

In one embodiment, R³⁶⁰ is

R³⁶⁶

R¹²¹ is

and R³¹⁶ is

In one embodiment, R³⁶⁰ is

R³⁶⁶ is

R¹²¹ is

and R³¹⁶ is

Non-limiting Examples of Compounds of Formula VIID include:

In certain embodiments of Formula VIID, x and x′ are independentlyselected from 1, 2, 3, 4, 5, or 6; y and y′ are independently selectedfrom 1, 2, 3, 4, 5, or 6; and z is independently selected at eachinstance from 1, 2, and 3.

In certain embodiments of Formula VIID, x and x′ are independentlyselected from 1, 2, or 3; y and y′ are independently selected from 1, 2,or 3; and z is independently selected at each instance from 1, 2, and 3.

In certain embodiments of Formula VIID, x and x′ are independentlyselected from 1, 2, or 3; y and y′ are independently selected from 1, 2,or 3; and z in at least one instance is 1.

In certain embodiments of Formula VIID, x and x′ are independentlyselected from 1, 2, or 3; y and y′ are independently selected from 1, 2,or 3; and z in at least one instance is 2.

In certain embodiments of Formula VIID, x and x′ are independentlyselected from 1, 2, or 3; y and y′ are independently selected from 1, 2,or 3; and z in at least one instance is 3.

In certain embodiments of Formula VIID, x and x′ are 1; y and y′ areindependently selected from 1, 2, or 3; and z is independently selectedat each instance from 1, 2, and 3.

In certain embodiments of Formula VIID, x and x′ are 2; y and y′ areindependently selected from 1, 2, or 3; and z is independently selectedat each instance from 1, 2, and 3.

In certain embodiments of Formula VIID, x and x′ are 3; y and y′ areindependently selected from 1, 2, or 3; and z is independently selectedat each instance from 1, 2, and 3.

In certain embodiments of Formula VIID, x and x′ are independentlyselected from 1, 2, or 3; y and y′ are 1; and z is independentlyselected at each instance from 1, 2, and 3.

In certain embodiments of Formula VIID, x and x′ are independentlyselected from 1, 2, or 3; y and y′ are 2; and z is independentlyselected at each instance from 1, 2, and 3.

In certain embodiments of Formula VIID, x and x′ are independentlyselected from 1, 2, or 3; y and y′ are 3; and z is independentlyselected at each instance from 1, 2, and 3.

Duel Leucine Zipper Kinase Prodrugs

The disclosure provides duel leucine zipper kinase prodrugs of FormulaIE:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R¹⁸ is selected from: —C(O)CH₂CH₂C₁₉-C₃₀alkylR⁵,—C(O)CH₂CH₂C₁₉-C₃₀alkenylR⁵, —C(O)CH₂CH₂C₁₉-C₃₀alkynylR⁵,—C(O)CH₂CH₂C₁₉-C₃₀alkenylalkynylR⁵, —C(O)CH₂CH₂C₁₉-C₃₀alkyl,—C(O)CH₂CH₂C₁₉-C₃₀alkenyl, —C(O)CH₂CH₂C₁₉-C₃₀alkynyl,—C(O)CH₂CH₂C₁₉-C₃₀alkenylalkynyl, and R¹⁹ wherein R¹⁸ can be furtheroptionally further substituted with R⁵ (including for example a secondR⁵) if valence permits, a stable compound is formed, and the resultingcompound is pharmaceutically acceptable;

In various different embodiments, —C₁₉-C₃₀ as used in the definition ofR¹⁸ is —C₁₉-C₂₈, —C₁₉-C₂₆, —C₁₉-C₂₄, —C₁₉-C₂₂, —C₁₉-C₂₀, —C₂₀-C₂₈,—C₂₀-C₂₆, —C₂₀-C₂₄, —C₂₀-C₂₂, —C₂₂- C₂₈, —C₂₂-C₂₆, —C₂₂-C₂₄, or—C₂₆-C₂₈.

R¹⁹ is selected from:

-   -   (i) an unsaturated fatty acid residue including but not limited        to the carbonyl fragment taken from docosahexaenoic acid        (—C(O)(CH₂)₂(CHCHCH₂)₆CH₃)), docosatetraenoic acid, euric acid,        or nervonic acid;    -   (ii) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, or poly(lactic-co-glycolic acid)        including:

or polyglycolic acid, or a polyester, polyamide, or other biodegradablepolymer, each of which can be capped to complete the terminal valence orto create a terminal ether.

The disclosure provides duel leucine zipper kinase prodrugs of FormulaIIE:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R²⁰ is selected from: —C(O)CH₂CH₂C₉-C₃₀alkylR⁵,—C(O)CH₂CH₂C₉-C₃₀alkenylR⁵, —C(O)CH₂CH₂C₉-C₃₀alkynylR⁵,—C(O)CH₂CH₂C₉-C₃₀alkenylalkynylR⁵, —C(O)CH₂CH₂C₉-C₃₀alkyl,—C(O)CH₂CH₂C₉-C₃₀alkenyl, —C(O)CH₂CH₂C₉-C₃₀alkynyl,—C(O)CH₂CH₂C₉-C₃₀alkenylalkynyl, and R²¹.

In one embodiment, —C₉-C₃₀ as used in the definition of R²⁰ is —C₁₀-C₂₈,—C₁₁-C₂₆, —C₁₁-C₂₄, —C₁₂-C₂₂, —C₁₂-C₂₀, —C₁₂-C₁₈, —C₁₂-C₁₆, or —C₁₂-C₁₄

R²¹ is selected from:

-   -   (i) an unsaturated fatty acid residue including but not limited        the carbonyl fragment taken from linoleic acid        (—C(O)(CH₂)₇(CH)₂CH₂(CH)₂(CH₂)₄CH₃)), docosahexaenoic acid        (—C(O)(CH₂)₂(CHCHCH₂)₆CH₃)), eicosapentaenoic acid        (—C(O)(CH₂)₃(CHCHCH₂)₅CH₃)), alpha-linolenic acid        (—C(O)(CH₂)₇(CHCHCH₂)₃CH₃)) stearidonic acid, y-linolenic acid,        arachidonic acid, docosatetraenoic acid, palmitoleic acid,        vaccenic acid, paullinic acid, oleic acid, elaidic acid, gondoic        acid, euric acid, nervonic acid and mead acid, each of which can        be further substituted with R⁵ if valence permits, a stable        compound is formed, and the resulting compound is        pharmaceutically acceptable;    -   (ii) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, and poly(lactic-co-glycolic acid)        including:

or polyglycolic acid, or a polyester, polyamide, or other biodegradablepolymer, each of which can be capped to complete the terminal valence orto create a terminal ether.

-   -   (iii) The disclosure provides duel leucine zipper kinase        prodrugs of Formula IIIE:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

Q is selected from: N, CH, and CR²³.

R²² is selected from: —C(O)CH₂CH₂C₁₁-C₃₀alkylR⁵,—C(O)CH₂CH₂C₁₁-C₃₀alkenylR⁵, —C(O)CH₂CH₂C₁₁-C₃₀alkynylR⁵,—C(O)CH₂CH₂C₁₁-C₃₀alkenylalkynylR⁵, —C(O)CH₂CH₂C₁₁-C₃₀alkyl,—C(O)CH₂CH₂C₁₁-C₃₀alkenyl, —C(O)CH₂CH₂C₁₁-C₃₀alkynyl,—C(O)CH₂CH₂C₁₁-C₃₀alkenylalkynyl and R²¹ and wherein R²² can be furthersubstituted with R⁵ (including for example a second R⁵) if valencepermits, a stable compound is formed, and the resulting compound ispharmaceutically acceptable.

In one embodiment, —C₁₁-C₃₀ as used in the definition of R²² is—C₁₂-C₂₈, —C₁₃-C₂₆, —C₁₃-C₂₄, —C₁₃-C₂₂, —C₁₃-C₂₀, —C₁₃-C₁₈, —C₁₃-C₁₆, or—C₁₃-C₁₄.

R²³, R²⁴, and R²⁵ are independently selected from: hydrogen, halogen,hydroxyl, cyano, mercapto, nitro, amino, aryl, alkyl, alkoxy, alkenyl,alkynyl cycloalkyl, cycloalkylalkyl, heterocyclyl, heterocycloalkyl,aryl, arylalkyl, heteroaryl, heteroarylalkyl, aryloxy, —S(O)₂alkyl,—S(O)alkyl, —P(O)(Oalkyl)₂, B(OH)₂, —Si(CH₃)₃, —COOH, —COOalkyl, —CONH₂,

each of which except halogen, nitro, and cyano, may be optionallysubstituted, for example with halogen, alkyl, aryl, heterocycle orheteroaryl.

R²⁶ is selected from H, C(O)A, —C₀-C₁₀alkylR⁵, —C₂-C₁₀alkenylR⁵,—C₂-C₁₀alkynylR⁵, —C₂-C₁₀alkenyl, and —C₂-C₁₀alkynyl.

In one embodiment, —C₂-C₁₀ as used in R²⁶ is —C₄-C₁₀, —C₆-C₁₀, or—C₈-C₁₀.

The disclosure also provides a prodrug of Formula IVE:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R²⁷ is selected from: —C(O)CH₂CH₂C₀-C₃₀alkylR⁵,—C(O)CH₂CH₂C₀-C₃₀alkenylR⁵, —C(O)CH₂CH₂C₀-C₃₀alkynylR⁵,—C(O)CH₂CH₂C₀-C₃₀alkenylalkynylR⁵, —C(O)CH₂CH₂C₀-C₃₀alkyl,—C(O)CH₂CH₂C₀-C₃₀alkenyl, —C(O)CH₂CH₂C₀-C₃₀alkynyl,—C(O)CH₂CH₂C₀-C₃₀alkenylalkynyl, and R²¹.

In various different embodiments, —C₀-C₃₀ as used in R²⁷ is —C₀-C₂₈,—C₀-C₂₆, —C₀-C₂₄, —C₀-C₂₂, —C₀-C₂₀, —C₀-C₁₈, —C₀-C₁₆, —C₀-C₁₄, —C₀-C₁₂,or —C₀-C₁₁, —C₀-C₁₀, —C₀-C₈, —C₀-C₆, —C₀-C₄, —C₀-C₂, —C₂-C₂₈, —C₄-C₂₆,—C₄-C₂₄, —C₄-C₂₂, —C₄-C₂₀, —C₆-C₁₈, —C₆-C₁₆, —C₆-C₁₄, —C₆-C₁₂, —C₄-C₁₁,—C₀-C₁₀, —C₀-C₈, —C₀-C₆, —C₀-C₄, or —C₀-C₂.

The disclosure also provides a prodrug of Formula VE, Formula VIE,Formula VIIE, Formula VIIIE, Formula IXE, and Formula XE:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R³⁹ is selected from: R⁴⁰, carbonyl linked polyethylene glycol, carbonyllinked polypropylene glycol, carbonyl linked polypropylene oxide,polylactic acid, and poly(lactic-co-glycolic acid), a polyglycolic acid,a polyester, polyamide,

or other biodegradable polymer, wherein each R³⁹ other than R⁴⁰ issubstituted with at least one L⁴-R¹²¹;

R⁴⁰ is selected from:

Rho Kinase (ROCK) Inhibitor Prodrugs

The disclosure provides ROCK inhibitor prodrugs of Formula IF, FormulaIIF, Formula IIIF, Formula IVF, and Formula VF:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

Z is CR¹³⁰ or N;

t is independently selected from 0, 1, 2, 3, and 4;

R¹³⁰, R¹³¹, and R¹³³ are independently selected at each occurrence fromH, C₁-C₃₀alkyl, —C(O)C₁-C₃₀alkyl, C₁-C₃₀heteroalkyl, and R¹³⁶;

R¹³² is selected from R¹³⁶, C₁-C₃₀alkyl, C₁-C₃₀cycloalkyl,heterocycloalkyl, aryl, heteroaryl, and alkylaryl, any of which can beoptionally substituted with one or more of hydroxyl, —CH₂OH, —C(O)NH₂,acetyl, carbonyl, alkyl, cycloalkyl, heterocycloalkyl, aryl, andheteroaryl, any of which can be optionally substituted with one or moreof hydroxyl, nitro, amino, —NR¹³⁴R¹³⁵, alkyl, alkoxy, alkylalkoxy,alkoxylalkoxy, haloalkoxy, heteroarylcarbonyl, heteroaryl, —OCH₃, —OCF₃,—OCHF₂, —OCH₂F, —OSO₂CH₃, tosyl, or halogen;

R¹⁴⁰ is selected from R¹³⁶, hydrogen, alkyl, cycloalkyl,heterocycloalkyl, and aryl, any of which except hydrogen can beoptionally substituted with one or more of hydroxyl, —CH₂OH, —C(O)NH₂,acetyl, carbonyl, alkyl, cycloalkyl, heterocycloalkyl, aryl, andheteroaryl, any of which can be optionally substituted with one or moreof hydroxyl, nitro, amino, —NR¹³⁴R¹³⁵, alkyl, alkoxy, alkylalkoxy,alkoxylalkoxy, haloalkoxy, heteroarylcarbonyl, heteroaryl, —OCH₃, —OCF₃,—OCHF₂, —OCH₂F, —OSO₂CH₃, tosyl, or halogen;

R¹³⁶ is selected from: R¹³⁷, acyl, alkyl, alkyloxy, polyethylene glycol,polypropylene glycol, polypropylene oxide, polylactic acid,poly(lactic-co-glycolic acid), a polyglycolic acid, a polyester,polyamide, or other biodegradable polymer, wherein each R¹³⁶ other thanR¹³⁷ is substituted with at least one L⁴-R¹²¹;

or R¹³⁶ is L⁴-R¹²¹ or R¹²¹;

wherein at least one of R¹³⁰, R¹³¹, and R¹³³ is R¹³⁶; and

-   -   R¹³⁷ is selected from:

andwherein all other variables are as defined herein.

In one embodiment, Formula IF is Formula IFa

wherein:

R¹⁴² and R¹⁴³ are independently selected from H, —OH, acetyl, —C(O)NH₂,C₁-C₆alkyl, C₁-C₆cycloalkyl, hereterocycloalkyl, aryl, or heteroaryl,wherein any one of the C₁-C₆alkyl, C₁-C₆cycloalkyl,hereteroC₁-C₆cycloalkyl, aryl, or heteroaryl groups is optionallysubstituted with one or more of hydroxyl, —CH₂OH, —C(O)NH₂, acetyl,carbonyl, alkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, anyof which can be optionally substituted with one or more of hydroxyl,nitro, amino, —NR¹³⁴R¹¹, alkyl, alkyl-O—R¹³⁶, alkoxy, alkylalkoxy,alkoxylalkoxy, heteroarylcarbonyl, heteroaryl, —OCH₃, —OCF₃, —OCHF₂,—OCH₂F;

R¹³⁹ is selected from cycloalkyl, heterocycloalkyl, aryl, or heteroaryl,any of which is optionally substituted with one or more of hydroxyl,—CH₂OH, —C(O)NH₂, acetyl, carbonyl, alkyl, cycloalkyl, heterocycloalkyl,aryl, and heteroaryl, any of which can be optionally substituted withone or more of hydroxyl, nitro, amino, —NR¹³⁴R¹³⁵, alkyl, alkoxy,alkylalkoxy, alkoxylalkoxy, haloalkoxy, heteroarylcarbonyl, heteroaryl,—OCH₃, —OCF₃, —OCHF₂, —OCH₂F, —OSO₂CH₃, tosyl, or halogen;

p is 1, 2, or 3; and

wherein all other variables are as defined herein.

In one embodiment, Formula IF is Formula IFb

wherein:

R²³⁰ and R²³¹ are independently selected at each occurrence from H,C₁-C₃₀alkyl, —C(O)C₁-C₃₀alkyl, C₁-C₃₀heteroalkyl, and R¹³⁶;

R²⁴² and R²⁴³ are independently selected at each instance from H, —OH,acetyl, —C(O)NH₂, C₁-C₆alkyl, C₁-C₆cycloalkyl, hereterocycloalkyl, aryl,or heteroaryl, wherein any one of the C₁-C₆alkyl, C₁-C₆cycloalkyl,hereteroC₁-C₆cycloalkyl, aryl, or heteroaryl groups is optionallysubstituted with one or more substituents selected from hydroxyl, nitro,amino, —NR¹³⁴R¹³⁵, alkyl, alkyl-O—R¹³⁶, —O—R¹³⁶, alkoxy, alkylalkoxy,alkoxylalkoxy, heteroarylcarbonyl, heteroaryl, —OCH₃, —OCF₃, —OCHF₂,—OCH₂F;

wherein at least one instance of R²³⁰, R²³¹, R²⁴², or R²⁴³ is R¹³⁶ orcontains a O—R¹³⁶ substituent; and

wherein all other variables are as defined herein.

In one embodiment the compound is:

wherein:

R^(230a) and R^(231a) are independently selected at each occurrence fromH, C₁-C₃₀alkyl, —C(O)C₁-C₃₀alkyl, and C₁-C₃₀heteroalkyl; and

wherein all other variables are as defined herein.

Non-limiting examples of Formula IF include

In one embodiment, Formula IIF is Formula IIFa

wherein all other variables are as defined herein.

In one embodiment, Formula IIF is Formula IIFb

wherein:

R²³⁰, R²³¹, and R²³³ are independently selected at each occurrence fromH, C₁-C₃₀alkyl, —C(O)C₁-C₃₀alkyl, C₁-C₃₀heteroalkyl, and R¹³⁶;

wherein at least one instance of R²³⁰, R²³¹, R²³³, R²⁴², or R²⁴³ is R¹³⁶or contains a O—R¹³⁶ substituent;

wherein all other variables are as defined herein.

Non-limiting examples of Formula IIF include

In one embodiment, Formula IIIF is Formula IIIFa

wherein all other variables are as defined herein.

In one embodiment, Formula IIIF is Formula IIIFb

wherein at least one instance of R²³⁰, R²³¹, R²⁴², or R²⁴³ is R¹³⁶ orcontains a O—R¹³⁶ substituent; and

wherein all other variables are as defined herein.

In one embodiment the compound is:

wherein all variables are as defined herein.

Non-limiting examples of Formula IIIF include

The disclosure provides ROCK inhibitor prodrugs of Formula VIF, FormulaVIIF, and Formula VIIIF:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R³⁰³, R³⁰⁴, and R³⁴⁴ are independently selected at each occurrence fromH, C₁-C₃₀alkyl, —C(O)C₁-C₃₀alkyl, C₂-C₃₀alkenyl, C₁-C₃₀heteroalkyl, andR³³⁶;

wherein at least one of R³⁰³, R³⁰⁴, and R³⁴⁴ is R³³⁶;

R³³⁶ is selected from:

and

wherein all other variables are as defined herein.

In one embodiment, R¹⁴¹ is OCH₃.

In one embodiment, R³⁰¹ is selected from —N(CH₃)₂,

In one embodiment, R³⁰¹ is

In one embodiment, R³⁰¹ is —OCH₃.

In one embodiment, R³⁰¹ is selected from F and Cl.

In one embodiment, R³⁰⁴ is hydrogen.

In one embodiment, R³⁰⁴ is CH₃.

In one embodiment, R³⁰⁴ is CH₂H₅.

In one embodiment, R³⁰³ is

In one embodiment, R³⁰³ is

and R¹²¹ is

In one embodiment, R³⁰³ is

and R¹²¹ is

In a further embodiment, x is 2 and z is 2.

Non-limiting Examples of Formula VIF and Formula VIIF include

The disclosure provides ROCK inhibitor prodrugs of Formula IXF, FormulaXF, and Formula XIF:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

Y is CR¹⁵⁰ or N;

R¹⁵⁰ and R¹⁵¹ are independently selected at each occurrence from H,C₁-C₃₀alkyl, —C(O)C₁-C₃₀alkyl, C₁-C₃₀heteroalkyl, and R¹⁵⁶;

R¹⁵² is selected from C₁-C₃₀alkyl, C₁-C₃₀cycloalkyl, heterocycloalkyl,aryl, heteroaryl, or alkylaryl, any of which can be optionallysubstituted with one or more of hydroxyl, —CH₂OH, —C(O)NH₂, acetyl,carbonyl, alkyl, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl, anyof which can be optionally substituted with one or more of hydroxyl,nitro, amino, —NR¹³⁴R¹³⁵, alkyl, alkoxy, alkylalkoxy, alkoxylalkoxy,haloalkoxy, heteroarylcarbonyl, heteroaryl, —OCH₃, —OCF₃, —OCHF₂,—OCH₂F, —OSO₂CH₃, tosyl, or halogen;

or R¹⁵¹ and R¹⁵² can together form a cycloalkyl or heterocycloalkyl;

R¹⁶⁰ is selected from H, C₁-C₃₀alkyl, C₁-C₃₀cycloalkyl,heterocycloalkyl, and aryl, any of which except hydrogen can beoptionally substituted with one or more of hydroxyl, —CH₂OH, —C(O)NH₂,acetyl, carbonyl, alkyl, cycloalkyl, heterocycloalkyl, aryl, andheteroaryl, any of which can be optionally substituted with one or moreof hydroxyl, nitro, amino, —NR¹³⁴R¹³⁵, alkyl, alkoxy, alkylalkoxy,alkoxylalkoxy, haloalkoxy, heteroarylcarbonyl, heteroaryl, —OCH₃, —OCF₃,—OCHF₂, —OCH₂F, —OSO₂CH₃, tosyl, or halogen; or R¹⁵¹ and R¹⁵² cantogether form a cycloalkyl or heterocycloalkyl;

wherein at least one of R¹⁵⁰ and R¹⁵¹ is R¹⁵⁶;

R¹⁵⁶ is selected from:

-   -   (i) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, poly(lactic-co-glycolic acid)        polyglycolic acid, polyester, polyamide, and other biodegradable        polymers, each of which can be capped to complete the terminal        valence or to create a terminal ether or ester, in one        embodiment the capping group is selected from R³¹¹; and

wherein all other variables are as defined herein.

In one embodiment R¹⁵⁶ is selected from:

The disclosure provides ROCK inhibitor prodrugs of Formula XIIF, FormulaXIIIF, and Formula XIVF:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R³⁰² and R³³³ are independently selected from H, C₁-C₃₀alkyl,—C(O)C₁-C₃₀alkyl, C₁-C₃₀heteroalkyl, C₂-C₃₀alkenyl, and R³⁵⁶;

R³⁵⁰ is selected from H, C₁-C₃₀alkyl, —C(O)C₁-C₃₀alkyl,C₁-C₃₀heteroalkyl, C₂-C₃₀alkenyl, and R³⁵⁶;

R³⁵⁶ is selected from

-   -   (i) polyethylene glycol, polypropylene glycol, polypropylene        oxide, polylactic acid, poly(lactic-co-glycolic acid)        polyglycolic acid, polyester, polyamide, and other biodegradable        polymers, each of which can be capped to complete the terminal        valence or to create a terminal ether or ester;

wherein at least one of R³⁰², R³³³ and R³⁵⁰ is R³⁵⁶; and

wherein all other variables are as defined herein.

In one embodiment, R¹⁴¹ is OCH₃.

In one embodiment, R³⁰¹ is selected from —N(CH₃)₂,

In one embodiment, R³⁰¹ is

In one embodiment, R³⁰¹ is —OCH₃.

In one embodiment, R³⁰¹ is selected from F and Cl.

In one embodiment, R³⁵⁰ is hydrogen.

In one embodiment, R³⁵⁰ is CH₃.

In one embodiment, R³⁵⁰ is CH₂H₅.

In one embodiment, R³⁵⁶ is

and R^(31a) is —C(O)CH₃.

In one embodiment, R³⁵⁶ is

and R^(31a) is stearoyl.

In one embodiment, R³⁵⁶ is

and R^(31a) is —C(O)CH₃.

In one embodiment, R³⁵⁶ is

and R^(31a) is —C(O)CH₃.

In one embodiment, R³⁵⁶ is

and x is an integer between 1 and 6.

In one embodiment, R³⁵⁶ is

and y is 11.

In one embodiment, R³⁵⁶ is

and y is 17.

In one embodiment, R³³³ is

and R^(31a) is —C(O)alkyl.

Non-limiting Examples of Formula XIF and Formula XIIF include

Beta-Blocker Prodrugs

The disclosure provides beta-blocker prodrugs of Formula IG, FormulaIIG, Formula IIIG, Formula IVG, Formula VG, Formula VIG, Formula VIIG,and Formula VIIIG:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R¹⁷⁰, R¹⁷¹, and R¹⁷² are independently selected from: R¹, R¹⁷³, acyl,carbonyl linked polyethylene glycol, carbonyl linked polypropyleneglycol, carbonyl linked polypropylene oxide, polylactic acid,poly(lactic-co-glycolic acid), polyglycolic acid, polyester, polyamide,or other biodegradable polymer, each of which R¹⁷⁰, R¹⁷¹, and R¹⁷² otherthan R¹⁷³ are optionally substituted with L⁸-R¹²¹;

wherein at least one of R¹⁷⁰, R¹⁷¹, and R¹⁷² is R¹⁷³ or substituted withL⁸-R¹²¹

R¹⁸⁰ is C₁-C₆ alkyl, acyl, or hydrogen;

R¹⁸¹ is selected from:

and R¹⁸⁵;

R¹⁸² is independently selected from alkyl, cycloalkyl, aryl, heteroaryl,heterocycle, cyano, amino, hydroxyl, and acyl, each of which R¹⁸² isoptionally substituted with a R¹⁷⁰ group;

R¹⁸³ is independently selected from alkyl, cycloalkyl, aryl, heteroaryl,heterocycle, amino, hydroxyl, and acyl;

or two R¹⁸³ groups with the carbon to which they are linked form acarbonyl group;

or two R¹⁸³ groups with the carbon(s) to which they are linked form afused or spirocyclic ring;

R¹⁸⁴ is selected from alkyl, cycloalkyl, R¹⁷⁰, and acyl;

R¹⁸⁵ is selected from aryl, heteroaryl, cycloalkyl, and heterocycle,wherein each R¹⁸⁵ is optionally substituted with 1, 2, 3, or 4 R¹⁸²groups;

R¹⁷³ is selected from:

and

-   -   wherein all other variables are defined herein.

The disclosure provides beta-blocker prodrugs of Formula IXG, FormulaXG, Formula IIIG, Formula XIG, Formula XIIG, Formula XIIIG, FormulaXIVG, Formula XVG, and Formula XVIG:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof wherein

R¹⁷⁵, R¹⁷⁶, and R¹⁷⁷ are independently selected from: C(O)A, C(O)R⁴, andR¹⁷⁸;

wherein at least one of R¹⁷⁵, R¹⁷⁶, and R¹⁷⁷ is R¹⁷⁸; and

wherein all other variables are as defined herein.

In some embodiments the compounds of Formula IXG to Formula XVIG can beused in the form of an R enantiomer, an S enantiomer, or a mixture ofenantiomers including a racemic mixture.

In some embodiments the compounds of Formula IXG to Formula XVIG havethe same stereochemistry as the corresponding commercial drug.

Loop Diuretic Prodrugs, Including Ethacrynic Acid Prodrugs

The disclosure provides ethacrynic acid prodrugs of Formula IH:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R⁶¹¹ is selected from:

-   -   (i) —C(O)OC₅-C₃₀alkylR⁵, —C(O)OC₂-C₃₀alkenylR⁵,        —C(O)OC₂-C₃₀alkynylR⁵, —C(O)OC₄-C₃₀alkenylalkynylR⁵,        —C(O)OC₅-C₃₀alkyl, —C(O)OC₂-C₃₀alkenyl, —C(O)OC₂-C₃₀alkynyl, and        —C(O)OC₄-C₃₀alkenylalkynyl;    -   (ii) —C(O)O(C₁₋₃₀alkyl with at least one R⁵ substituent on the        alkyl chain, —C(O)O(C₁₋₃₀alkenyl, with at least one R⁵        substituent on the alkenyl chain, and —C(O)O(C₁₋₃₀alkynyl, with        at least one R⁵ substituent on the alkynyl chain;    -   (iii) —C(O)(OCH₂C(O))₁₋₂₀OC₁₋₃₀alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₂₀OC₁₋₃₀alkyl,        —C(O)(OCH₂C(O))₁₋₁₀OC₁₋₃₀alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₁₀OC₁₋₃₀alkyl,        —C(O)(OCH₂C(O))₄₋₂₀OC₁₋₃₀alkyl,        —C(O)(OCH(CH₃)C(O))₄₋₂₀OC₁₋₃₀alkyl,        —C(O)(OCH₂C(O))₁₋₂₀OC₁₋₁₀alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₂₀OC₁₋₁₀alkyl,        —C(O)(OCH₂C(O))₁₋₂₀OC₄₋₁₀alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₂₀OC₄₋₁₀alkyl, —C(O)(OCH₂C(O))₁₋₂₀OH,        —C(O)(OCH(CH₃)C(O))₁₋₂₀OH, —C(O)(OCH₂C(O))₁₋₁₀OH,        —C(O)(OCH(CH₃)C(O))₁₋₁₀OH, —C(O)(OCH₂C(O))₄₋₂₀OH,        —C(O)(OCH(CH₃)C(O))₄₋₂₀OH, —C(O)(OCH₂C(O))₄₋₁₀OH,        —C(O)(OCH(CH₃)C(O))₄₋₁₀OH, —C(O)(OCH(CH₃)C(O))₄₋₁₀OC₁₋₁₀alkyl,        —C(O)(OCH₂C(O))₄₋₁₀OC₁₋₁₀alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₁₀OC₁₋₁₀alkyl,        —C(O)(OCH₂C(O))₁₋₁₀OC₁₋₁₀alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₁₀OC₄₋₁₀alkyl,        —C(O)(OCH₂C(O))₁₋₁₀OC₄₋₁₀alkyl, —C(O)(OCH₂C(O))₁₋₁₀OC₄₋₁₀alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₁₀OC₄₋₁₀alkyl,        —C(O)(OCH₂C(O))₁₋₁₀OC₄₋₁₀alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₁₀OC₄₋₁₀alkyl,        —C(O)(OCH₂C(O))₁₋₁₀(OCH(CH₃)C(O))₁₋₁₀OC₁₋₃₀alkyl,        —C(O)(OCH₂C(O))₂₋₁₀(OCH(CH₃)C(O))₂₋₁₀OC₁₋₃₀alkyl,        —C(O)(OCH₂C(O))₁₋₁₀(OCH(CH₃)C(O))₁₋₁₀OC₁₋₁₂alkyl,        —C(O)(OCH₂C(O))₁₋₁₀(OCH(CH₃)C(O))₁₋₁₀OC₄₋₂₂alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₁₀(OCH₂C(O))₁₋₁₀OC₁₋₃₀alkyl,        —C(O)(OCH(CH₃)C(O))₂₋₁₀(OCH₂C(O))₂₋₁₀OC₁₋₃₀alkyl,        —C(O)(OCH(CH₃)C(O))₁₋₁₀(OCH₂C(O))₁₋₁₀OC₁₋₁₂alkyl, and        —C(O)(OCH(CH₃)C(O))₁₋₁₀(OCH₂C(O))₁₋₁₀OC₄₋₂₂alkyl;    -   (iv) polypropylene glycol, polypropylene oxide, polylactic acid,        poly(lactic-co-glycolic acid), polyglycolic acid, polyester,        polyamide, and other biodegradable polymers, each of which can        be capped to complete the terminal valence or to create a        terminal ether or ester; and

R⁶²⁰ is hydrogen, alkyl, alkenyl, alkynyl cycloalkyl, cycloalkylalkyl,heterocyclyl, heterocycloalkyl, aryl, arylalkyl, heteroaryl, orheteroarylalkyl, each of which except hydrogen, may be optionallysubstituted, for example with halogen, alkyl, aryl, heterocycle orheteroaryl if desired and if the resulting compound is stable andachieves the desired purpose, wherein the group cannot be substitutedwith itself, for example alkyl would not be substituted with alkyl;

tt is any integer between 4 and 10 (4, 5, 6, 7, 8, 9, or 10); and

wherein all other integers are as defined herein.

In one embodiment, x, y, and z are independently an integer between 1and 12 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12).

In one embodiment, x, y, and z are independently an integer between 1and 10 (1, 2, 3, 4, 5, 6, 7, 8, 9, or 10).

In one embodiment, x, y, and z are independently an integer between 1and 8 (1, 2, 3, 4, 5, 6, 7, or 8).

In one embodiment, x, y, and z are independently an integer between 1and 6 (1, 2, 3, 4, 5, or 6).

In one embodiment, x, y, and z are independently an integer between 4and 10 (4, 5, 6, 7, 8, 9, or 10).

In one embodiment, x is an integer between 1 and 12 (1, 2, 3, 4, 5, 6,7, 8, 9, 10, 11, or 12) and y is an integer between 1 and 6 (1, 2, 3, 4,5, or 6).

In one embodiment, y is an integer between 1 and 12 (1, 2, 3, 4, 5, 6,7, 8, 9, 10, 11, or 12) and x is an integer between 1 and 6 (1, 2, 3, 4,5, or 6).

In one embodiment, x is an integer between 1 and 6 (1, 2, 3, 4, 5, or 6)and y is an integer between 1 and 3 (1, 2, or 3).

In one embodiment, y is an integer between 1 and 6 (1, 2, 3, 4, 5, or 6)and x is an integer between 1 and 3 (1, 2, or 3).

In one embodiment x is 1 and y is 1.

In one embodiment x is 1 and y is 2.

In one embodiment x is 1 and y is 3.

In one embodiment x is 1 and y is 4.

In one embodiment x is 1 and y is 5.

In one embodiment x is 1 and y is 6.

In one embodiment x is 1 and y is 7.

In one embodiment x is 1 and y is 8.

In one embodiment x is 2 and y is 1.

In one embodiment x is 2 and y is 2.

In one embodiment x is 2 and y is 3.

In one embodiment x is 2 and y is 4.

In one embodiment x is 2 and y is 5.

In one embodiment x is 2 and y is 6.

In one embodiment x is 2 and y is 7.

In one embodiment x is 2 and y is 8.

In certain embodiments, x and y are independently selected from 1, 2, 3,4, 5, or 6, and z is 1.

In certain embodiments, x and y are independently selected from 1, 2, 3,4, 5, or 6, and z is 2.

In one embodiment, R⁶¹¹ is

In one embodiment, R⁶¹¹ is

In one embodiment, R⁶¹¹ is

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄₋₂₀OCH₂CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₀CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₆CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄OCH₂CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄O(CH₂)₁₀CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄OCH₂)₁₆CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₆COCH₂CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₆O(CH₂)₁₀CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₆O(CH₂)₁₆CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₈OOCH₂CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₈O(CH₂)₁₀CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₈O(CH₂)₁₆CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₉₋₁₇CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₁₋₁₇CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₃₋₁₇CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₅₋₁₇CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₁CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₇CH₃.

In one embodiment, R⁶¹¹ is —C(O)(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀OCH₂CH₃.

In one embodiment, R⁶¹¹ is—C(O)(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₁CH₃.

In one embodiment, R⁶¹¹ is—C(O)(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₇CH₃.

In one embodiment, R⁶¹¹ is—C(O)(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₉₋₁₇CH₃.

In one embodiment, R⁶¹¹ is

—C(O)(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₁₋₁₇CH₃.

In one embodiment, R⁶¹¹ is—C(O)(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₃₋₁₇CH₃.

In one embodiment, R⁶¹¹ is—C(O)(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₅₋₁₇CH₃.

In one embodiment, C₁₋₃₀alkyl as used in the definition of R⁶¹¹ isC₁₋₂₈, C₁₋₂₆, C₁₋₂₄, C₁₋₂₂, C₁₋₂₀, C₁₋₁₈, C₁₋₁₆, C₁₋₁₄, C₁₋₁₂, C₁₋₁₀,C₁₋₈, C₁₋₆, or C₁₋₄.

The disclosure provides ECA prodrugs of Formula IIH and Formula IIIH:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R⁶¹³ is selected from:

R¹²² is selected from:

wherein all other variables are as defined herein.

In one embodiment of Formula IIH, R⁶¹³ is

and x is 4.

In one embodiment of Formula IIH, R¹²¹ is selected from

In one embodiment, x and y are independently an integer between 1 and 12(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12).

In one embodiment, x and y are independently an integer between 1 and 10(1, 2, 3, 4, 5, 6, 7, 8, 9, or 10).

In one embodiment, x and y are independently an integer between 1 and 8(1, 2, 3, 4, 5, 6, 7, or 8).

In one embodiment, x and y are independently an integer between 1 and 6(1, 2, 3, 4, 5, or 6).

In one embodiment, x and y are independently an integer between 4 and 10(4, 5, 6, 7, 8, 9, or 10).

In one embodiment, x is an integer between 1 and 12 (1, 2, 3, 4, 5, 6,7, 8, 9, 10, 11, or 12) and y is an integer between 1 and 6 (1, 2, 3, 4,5, or 6).

In one embodiment, y is an integer between 1 and 12 (1, 2, 3, 4, 5, 6,7, 8, 9, 10, 11, or 12) and x is an integer between 1 and 6 (1, 2, 3, 4,5, or 6).

In one embodiment, x is an integer between 1 and 6 (1, 2, 3, 4, 5, or 6)and y is an integer between 1 and 3 (1, 2, or 3).

In one embodiment, y is an integer between 1 and 6 (1, 2, 3, 4, 5, or 6)and x is an integer between 1 and 3 (1, 2, or 3).

In one embodiment x is 1 and y is 1.

In one embodiment x is 1 and y is 2.

In one embodiment x is 1 and y is 3.

In one embodiment x is 1 and y is 4.

In one embodiment x is 1 and y is 5.

In one embodiment x is 1 and y is 6.

In one embodiment x is 1 and y is 7.

In one embodiment x is 1 and y is 8.

In one embodiment x is 2 and y is 1.

In one embodiment x is 2 and y is 2.

In one embodiment x is 2 and y is 3.

In one embodiment x is 2 and y is 4.

In one embodiment x is 2 and y is 5.

In one embodiment x is 2 and y is 6.

In one embodiment x is 2 and y is 7.

In one embodiment x is 2 and y is 8.

The disclosure provides loop diuretic prodrugs of Formula IVH, FormulaVH, Formula VIH, Formula VIIH, and Formula VIIIH:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R⁷⁰¹ is selected from:

-   -   (i) -OC₁₅-C₃₀alkylR⁵, —OC₂-C₃₀alkenylR⁵, —OC₂-C₃₀alkynylR⁵,        —OC₄-C₃₀alkenylalkynylR⁵, —OC₁₅-C₃₀alkyl, —OC₂-C₃₀alkenyl,        —OC₂-C₃₀alkynyl, and —OC₄-C₃₀alkenylalkynyl;    -   (ii) —OC₁₅₋₃₀alkyl with at least one R⁵ substituent on the alkyl        chain, —OC₁₋₃₀alkenyl with at least one R⁵ substituent on the        alkenyl chain, and —OC₁₋₃₀alkynyl with at least one R⁵        substituent on the alkynyl chain;    -   (iii) —(OCH₂C(O))₁₋₂₀OC₁₋₃₀alkyl,        —(OCH(CH₃)C(O))₁₋₂₀OC₁₋₃₀alkyl, —(OCH₂C(O))₁₋₁₀OC₁₋₃₀alkyl,        —(OCH(CH₃)C(O))₁₋₁₀OC₁₋₃₀alkyl, —(OCH₂C(O))₄₋₂₀OC₁₋₃₀alkyl,        —(OCH(CH₃)C(O))₄₋₂₀OC₁₋₃₀alkyl, —(OCH₂C(O))₁₋₂₀OC₁₋₁₀alkyl,        —(OCH(CH₃)C(O))₁₋₂₀OC₁₋₁₀alkyl, —(OCH₂C(O))₁₋₂₀OC₄₋₁₀alkyl,        —(OCH(CH₃)C(O))₁₋₂₀OC₄₋₁₀alkyl, —(OCH₂C(O))₁₋₂₀OH,        —(OCH(CH₃)C(O))₁₋₂₀OH, —(OCH₂C(O))₁₋₁₀OH, —(OCH(CH₃)C(O))₁₋₁₀OH,        —(OCH₂C(O))₄₋₂₀OH, —(OCH(CH₃)C(O))₄₋₂₀OH, —(OCH₂C(O))₄₋₁₀OH,        —(OCH(CH₃)C(O))₄₋₁₀OH, —(OCH(CH₃)C(O))₄₋₁₀OC₁₋₁₀alkyl,        —(OCH₂C(O))₄₋₁₀OC₁₋₁₀alkyl, —(OCH(CH₃)C(O))₁₋₁₀OC₁₋₁₀alkyl,        —(OCH₂C(O))₁₋₁₀OC₁₋₁₀alkyl, —(OCH(CH₃)C(O))₁₋₁₀OC₄₋₁₀alkyl,        —(OCH₂C(O))₁₋₁₀OC₄₋₁₀alkyl, —(OCH₂C(O))₁₋₁₀OC₄₋₁₀alkyl,        —(OCH(CH₃)C(O))₁₋₁₀OC₄₋₁₀alkyl, —(OCH₂C(O))₁₋₁₀OC₄₋₁₀alkyl,        —(OCH(CH₃)C(O))₁₋₁₀OC₄₋₁₀alkyl,        —(OCH₂C(O))₁₋₁₀(OCH(CH₃)C(O))₁₋₁₀OC₁₋₃₀alkyl,        —(OCH₂C(O))₂₋₁₀(OCH(CH₃)C(O))₂₋₁₀OC₁₋₃₀alkyl,        —(OCH₂C(O))₁₋₁₀(OCH(CH₃)C(O))₁₋₁₀OC₁₋₁₂alkyl,        —(OCH₂C(O))₁₋₁₀(OCH(CH₃)C(O))₁₋₁₀OC₄₋₂₂alkyl,        —(OCH(CH₃)C(O))₁₋₁₀(OCH₂C(O))₁₋₁₀OC₁₋₃₀alkyl,        —(OCH(CH₃)C(O))₂₋₁₀(OCH₂C(O))₂₋₁₀OC₁₋₃₀alkyl,        —(OCH(CH₃)C(O))₁₋₁₀(OCH₂C(O))₁₋₁₀OC₁₋₁₂alkyl, and        —(OCH(CH₃)C(O))₁₋₁₀(OCH₂C(O))₁₋₁₀OC₄₋₂₂alkyl;    -   (iv) polypropylene glycol, polypropylene oxide, polylactic acid,        poly(lactic-co-glycolic acid), polyglycolic acid, a polyester, a        polyamide, and other biodegradable polymers, each of which can        be capped to complete the terminal valence or to create a        terminal ether or ester;

and

(v) —OH;

wherein R⁷⁰¹ cannot be OH when R⁷⁵¹ and R⁷⁵² are both hydrogen;

R⁷⁵¹ and R⁷⁵² are independently selected from hydrogen,

and

wherein all other variables are as defined herein.

In certain embodiments, x and y are independently selected from 1, 2, 3,4, 5, 6, 7, 8, 9, and 10.

In certain embodiments, x and y are independently selected from 1, 2, 3,4, 5, and 6.

In certain embodiments, x and y are independently selected from 1, 2, 3,4, 5, and 6.

In certain embodiments, x and y are independently selected from 1, 2, 3,and 4.

In certain embodiments, x and y are independently selected from 1, 2,and 3.

In certain embodiments, x is selected from 1, 2, 3, 4, 5, and 6 and y isselected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12.

In certain embodiments, y is selected from 1, 2, 3, 4, 5, and 6 and x isselected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12.

In certain embodiments, x is selected from 1, 2, 3, 4, 5, and 6 and y isselected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12.

In certain embodiments, y is selected from 1, 2, 3, 4, 5, and 6 and x isselected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12.

In certain embodiments, x is selected from 1, 2, and 3 and y is selectedfrom 1, 2, 3, 4, 5, and 6.

In certain embodiments, x is selected from 1, 2, 3, 4, 5, and 6, and yis selected from 1, 2, and 3.

In certain embodiments, x is selected from 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11, and 12 and xx is selected from 1, 2, 3, 4, 5, and 6.

In certain embodiments, x is selected from 1, 2, 3, 4, 5, and 6 and xxis selected from 1, 2, and 3.

In certain embodiments, x is 1, 2, or 3 and xx is 1.

In certain embodiments, x is 1, 2, or 3 and xx is 2.

In certain embodiments, x is 1, 2, or 3 and xx is 3.

In one embodiment, R⁷⁰¹ is

In one embodiment, R⁷⁰¹ is

In one embodiment, R⁷⁰¹ is

In one embodiment, R⁷⁰¹ is

In one embodiment, R⁷⁰¹ is

In one embodiment, R⁷⁰¹ is

In one embodiment, R⁷⁰¹ is

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄₋₂₀OCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄OCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄O(CH₂)₁₁CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄OCH₂)₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₆COCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₆O(CH₂)₁₁CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₆O(CH₂)₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₈OOCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₈O(CH₂)₁₁CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₈O(CH₂)₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH₂C(O))(OCH(CH₃)C(O))₄₋₂₀OCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH₂C(O))₂(OCH(CH₃)C(O))₄₋₂₀OCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH₂C(O))(OCH(CH₃)C(O))₄₋₁₀OCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH₂C(O))₂(OCH(CH₃)C(O))₄₋₁₀OCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH₂C(O))(OCH(CH₃)C(O))₆OCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH₂C(O))₂(OCH(CH₃)C(O))₆OCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₉₋₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₁₋₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₃₋₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₅₋₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₁CH₃.

In one embodiment, R⁷⁰¹ is —(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₇CH₃.

In one embodiment, R⁷⁰¹ is —(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀OCH₂CH₃.

In one embodiment, R⁷⁰¹ is —(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₁CH₃.

In one embodiment, R⁷⁰¹ is —(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₇CH₃.

In one embodiment, R⁷⁰¹ is—(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₉₋₁₇CH₃.

In one embodiment, R⁷⁰¹ is—(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₁₋₁₇CH₃.

In one embodiment, R⁷⁰¹ is—(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₃₋₁₇CH₃.

In one embodiment, R⁷⁰¹ is—(OCH₂C(O))₁₋₂(OCH(CH₃)C(O))₄₋₂₀O(CH₂)₁₅₋₁₇CH₃.

In one embodiment, C₁₋₃₀alkyl as used in the definition of R⁷⁰¹ isC₁₋₂₈, C₁₋₂₆, C₁₋₂₄, C₁₋₂₂, C₁₋₂₀, C₁₋₁₈, C₁₋₁₆, C₁₋₁₄, C₁₋₁₂, C₁₋₁₀,C₁₋₈, C₁₋₆, or C₁₋₄.

In one embodiment the prodrug of Formula IVH, Formula VH, or Formula VIHis selected from:

The disclosure provides loop diuretic prodrugs of Formula IXH, FormulaXH, Formula XIH, Formula XIIH, and Formula XIIIH:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

R⁷⁴⁰ is selected from:

and

-   -   (ii) —OH

wherein R⁷⁴⁰ cannot be —OH when R⁶¹ and R⁶² are both hydrogen;

R⁶¹ and R⁶² are independently selected from hydrogen

wherein all other variables are as defined herein.

In one embodiment R⁷⁴⁰ is

and R¹²¹ is

In one embodiment, R⁷⁴⁰ is

and R¹²¹ is

In one embodiment, R⁷⁴⁰ is

and R¹²¹ is

In one embodiment, R⁷⁴⁰ is selected from

and R¹²¹ is

In certain embodiments, x and y are independently selected from 1, 2, 3,4, 5, and 6.

In certain embodiments, x and y are independently selected from 1, 2, 3,and 4.

In certain embodiments, x and y are independently selected from 1, 2,and 3.

In certain embodiments, x is selected from 1, 2, 3, 4, 5, and 6 and y isselected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12.

In certain embodiments, y is selected from 1, 2, 3, 4, 5, and 6 and x isselected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12.

In certain embodiments, x is selected from 1, 2, and 3 and y is selectedfrom 1, 2, 3, 4, 5, and 6.

In certain embodiments, x is selected from 1, 2, 3, 4, 5, and 6, and yis selected from 1, 2, and 3.

In certain embodiments, x is selected from 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11, and 12 and xx is selected from 1, 2, 3, 4, 5, and 6.

In certain embodiments, x is selected from 1, 2, 3, 4, 5, and 6 and z isselected from 1, 2, and 3.

In certain embodiments, x is 1, 2, or 3 and z is 1.

In certain embodiments, x is 1, 2, or 3 and z is 2.

In certain embodiments, x is 1, 2, or 3 and z is 3.

In one embodiment the prodrug of Formula IXH, Formula XH, or Formula XIHis selected from:

The disclosure provides loop diuretic prodrugs of Formula XIVH, FormulaXVH, Formula XVIH, Formula XVIIH, Formula XVIIIH, and Formula XIXH:

or a pharmaceutically acceptable composition, salt, or isotopicderivative thereof.

wherein:

R²⁹ is selected from:

R²⁶⁴ is

a, b, and c are independently an integer selected from 0 to 30 (0, 1, 2,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,23, 24, 25, 26, 27, 28, 29, or 30) wherein a and c cannot both be 0; and

wherein all other variables are as defined herein.

The polymer moieties described in Formula XIIC, Formula IXD, Formula XD,Formula XID, Formula XIID, and Formula XIID′ above are depicted as blockcopolymers (for example, blocks of “a” followed by blocks of “b”followed by blocks of “c”), but it is intended that the polymer can be arandom or alternating copolymer (for example, “a” “b” and “c” are eitherrandomly distributed or alternate).

In one embodiment, a, b, and c are independently selected from aninteger between 1 and 12(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12).

In one embodiment, a, b, and c are independently selected from aninteger between 1 and 8 (1, 2, 3, 4, 5, 6, 7, or 8).

In one embodiment, a, b, and c are independently selected from aninteger between 1 and 6 (1, 2, 3, 4, 5, or 6).

In one embodiment, a, b, and c are independently selected from aninteger between 1 and 3 (1, 2, or 3).

In one embodiment, a and c are independently selected from an integerbetween 1 and 6 (1, 2, 3, 4, 5, or 6) and bis 1.

In one embodiment, a and c are independently selected from an integerbetween 1 and 3 (1, 2, or 3) and b is 1.

In one embodiment, a and c are independently selected from an integerbetween 1 and 12 (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) and b isselected from an integer between 1 and 6 (1, 2, 3, 4, 5, or 6).

In one embodiment, a and c are independently selected from an integerbetween 1 and 6 (1, 2, 3, 4, 5, or 6) and b is selected from an integerbetween 1 and 3 (1, 2, or 3).

In one embodiment, a and c independently selected from an integerbetween 1, 2, 3, and 4 and b is 1.

In one embodiment, a and c are 2 and b is 1.

In one embodiment, a and c are 3 and b is 1.

In one embodiment, a and c are 4 and b is 1.

In one embodiment the prodrug of Formula XVH, Formula XVIH or FormulaXVIIH is selected from:

Table A-Table I show illustrative prodrugs encapsulated in themicroparticles of the present invention. In one aspect of the invention,a mildly surface-treated microparticle comprising one of morebiodegradable polymers and a prodrug selected from Table A-Table Iencapsulated in the biodegradable polymer is provided.

An aspect of the invention is a method for the treatment of a disorder,comprising administering to a host in need thereof solid aggregatingmicroparticles comprising an effective amount of a therapeutic agentselected from a prodrug disclosed herein, wherein the therapeutic agentcontaining solid aggregating microparticles are injected into the bodyand aggregate in vivo to form at least one pellet of at least 500 μmthat provides sustained drug delivery for at least one month.

TABLE A Non-limiting Examples of Prodrugs Comp. # Structure 1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

TABLE B Non-limiting Examples of Prodrugs 45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

TABLE C Non-limiting Examples of Prodrugs  97

 98

 99

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

TABLE D Non-limiting Examples of Prodrugs 205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

TABLE E Select Compounds of the Present Invention 284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

TABLE F Compounds of the Present Invention Compd No. Structure 321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

TABLE G Compounds of the Present Invention 348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

TABLE H Additional Compounds of the Present Invention 363

364

365

366

367

TABLE I Additional Compounds of the Present Invention 368

369

370

371

372

373

374

375

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound of formula:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound of formula:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound selected from:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound selected from:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound selected from:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound selected from:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneof more biodegradable polymers and a compound of formula:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound selected from:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound selected from:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound selected from:

encapsulated in the biodegradable polymer is provided.

In one embodiment, a mildly surface-treated microparticle comprising oneor more biodegradable polymers and a compound selected from:

encapsulated in the biodegradable polymer is provided.

VII. Pharmaceutically Acceptable Carriers

Any suitable pharmaceutically acceptable carrier, for example,ophthalmically acceptable viscous carrier, may be employed in accordancewith the invention. The carrier is present in an amount effective inproviding the desired viscosity to the drug delivery system.Advantageously, the viscous carrier is present in an amount in a rangeof from about 0.5 wt percent to about 95 wt percent of the drug deliveryparticles. The specific amount of the viscous carrier used depends upona number of factors including, for example and without limitation, thespecific viscous carrier used, the molecular weight of the viscouscarrier used, the viscosity desired for the present drug delivery systembeing produced and/or used and like factors. Examples of useful viscouscarriers include, but are not limited to, hyaluronic acid, sodiumhyaluronate, carbomers, polyacrylic acid, cellulosic derivatives,polycarbophil, polyvinylpyrrolidone, gelatin, dextrin, polysaccharides,polyacrylamide, polyvinyl alcohol (which can be partially hydrolyzedpolyvinyl acetate), polyvinyl acetate, derivatives thereof and mixturesthereof.

The carrier can also be an aqueous carrier. Example of aqueous carriersinclude, but are not limited to, an aqueous solution or suspension, suchas saline, plasma, bone marrow aspirate, buffers, such as Hank'sBuffered Salt Solution (HBSS), HEPES(4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid), Ringers buffer,ProVisc®, diluted ProVisc®, ProVisc® diluted with PBS, Krebs buffer,Dulbecco's PBS, normal PBS; sodium hyaluronate solution (HA, 5 mg/mL inPBS), simulated body fluids, plasma platelet concentrate and tissueculture medium or an aqueous solution or suspension comprising anorganic solvent.

In one embodiment, the carrier is PBS.

In one embodiment, the carrier is HA, 5 mg/mL in PBS.

In one embodiment, the carrier is ProVisc® diluted with water.

In one embodiment, the carrier is ProVisc® dilution in PBS.

In one embodiment, the carrier is ProVisc® 5-fold diluted with water.

In one embodiment, the carrier is ProVisc® 5-fold dilution in PBS.

In one embodiment, the carrier is ProVisc® 10-fold diluted with water.

In one embodiment, the carrier is ProVisc® 10-fold dilution in PBS.

In one embodiment, the carrier is ProVisc® 20-fold dilution with water.

In one embodiment, the carrier is ProVisc® 20-fold dilution in PBS.

In one embodiment, the carrier is HA, 1.25 mg/mL in an isotonic buffersolution with neutral pH.

In one embodiment, the carrier is HA, 0.625 mg/mL in an isotonic buffersolution with neutral pH.

In one embodiment, the carrier is HA, 0.1-5.0 mg/mL in PBS.

In one embodiment, the carrier is HA, 0.5-4.5 mg/mL in PBS.

In one embodiment, the carrier is HA, 1.0-4.0 mg/mL in PBS.

In one embodiment, the carrier is HA, 1.5-3.5 mg/mL in PBS.

In one embodiment, the carrier is HA, 2.0-3.0 mg/mL in PBS.

In one embodiment, the carrier is HA, 2.5-3.0 mg/mL in PBS.

The carrier may, optionally, contain one or more suspending agent. Thesuspending agent may be selected from carboxy methylcellulose (CMC),mannitol, polysorbate, poly propylene glycol, poly ethylene glycol,gelatin, albumin, alginate, hydroxyl propyl methyl cellulose (HPMC),hydroxyl ethyl methyl cellulose (HEMC), bentonite, tragacanth, dextrin,sesame oil, almond oil, sucrose, acacia gum and xanthan gum andcombinations thereof.

The carrier may, optionally, contain one or more plasticizers. Thus thecarrier may also include a plasticizer. The plasticizer may, forexample, be polyethylene glycol (PEG), polypropylene glycol, poly(lactic acid) or poly (glycolic acid) or a copolymer thereof,polycaprolactone, and low molecule weight oligomers of these polymers,or conventional plasticizers, such as, adipates, phosphates, phthalates,sabacates, azelates and citrates. The carrier can also include otherknown pharmaceutical excipients in order to improve the stability of theagent.

In one embodiment, one or more additional excipients or deliveryenhancing agents may also be included e.g., surfactants and/orhydrogels, in order to further influence release rate.

VIII. Sustained Release of Pharmaceutically Active Compound

The rate of release of the pharmaceutically active compound can berelated to the concentration of pharmaceutically active compounddissolved in the surface treated microparticle. In some embodiments, thepolymeric composition of the surface treated microparticle includesnon-therapeutic agents that are selected to provide a desired solubilityof the pharmaceutically active compound. The selection of the polymericcomposition can be made to provide the desired solubility of thepharmaceutically active compound in the surface treated microparticle,for example, a hydrogel may promote solubility of a hydrophilicmaterial. In some embodiments, functional groups can be added to thepolymer to increase the desired solubility of the pharmaceuticallyactive compound in the surface treated microparticle. In someembodiments, additives may be used to control the release kinetics ofthe pharmaceutically active compound, for example, the additives may beused to control the concentration of the pharmaceutically activecompound by increasing or decreasing the solubility of thepharmaceutically active compound in the polymer so as to control therelease kinetics of the pharmaceutically active compound. The solubilitymay be controlled by including appropriate molecules and/or substancesthat increase and/or decrease the solubility of the dissolved form ofthe pharmaceutically active compound in the surface treatedmicroparticle. The solubility of the pharmaceutically active compoundmay be related to the hydrophobic and/or hydrophilic properties of thesurface treated microparticle and the pharmaceutically active compound.Oils and hydrophobic molecules can be added to the polymer(s) toincrease the solubility of a pharmaceutically active compound in thesurface treated microparticle.

Instead of, or in addition to, controlling the rate of migration basedon the concentration of the pharmaceutically active compound dissolvedin the surface treated microparticle, the surface area of the polymericcomposition can be controlled to attain the desired rate of drugmigration out of the surface treated microparticle comprising apharmaceutically active compound. For example, a larger exposed surfacearea will increase the rate of migration of the pharmaceutically activecompound to the surface, and a smaller exposed surface area willdecrease the rate of migration of the pharmaceutically active compoundto the surface. The exposed surface area can be increased in any numberof ways, for example, by castellation of the exposed surface, a poroussurface having exposed channels connected with the tear or tear film,indentation of the exposed surface, or protrusion of the exposedsurface. The exposed surface can be made porous by the addition of saltsthat dissolve and leave a porous cavity once the salt dissolves. In thepresent invention, these trends can be used to decrease the release rateof the active material from the polymeric composition by avoiding thesepaths to quicker release. For example, the surface area can beminimized, or channels can be avoided.

Where more than one type of polymer is used, each surface treatedmicroparticle may have a different solidifying or setting property. Forexample, the surface treated microparticles may be made from similarpolymers but may have different gelling pHs or different meltingtemperatures or glass transition points.

In order for the surface treated microparticles to form a consolidatedaggregate, the temperature around the particles, for example in thehuman or non-human animal where the composition is administered, isapproximately equal to, or greater than, the glass transitiontemperature (T_(g)) of the polymer particles. At such temperatures thepolymer particles will cross-link to one or more other polymer particlesto form a consolidated aggregate. By cross-link it is meant thatadjacent polymer particles become joined together. For example, theparticles may cross-link due to entanglement of the polymer chains atthe surface of one particle with polymer chains at the surface ofanother particle. There may be adhesion, cohesion or fusion betweenadjacent particles.

Typically, the injectable surface treated microparticles which areformed of a polymer or a polymer blend have a glass transitiontemperature (T_(g)) either close to or just above body temperature (suchas from about 30° C. to 45° C., e.g., from about 35° C. to 40° C., forexample, from about 37° C. to 40° C.). Accordingly, at room temperaturethe surface treated microparticles are below their T_(g) and behave asdiscrete particles, but in the body the surface treated microparticlessoften and interact/stick to themselves. Typically, agglomeration beginswithin 20 seconds to about 15 minutes of the raise in temperature fromroom to body temperature.

The surface treated microparticles may be formed from a polymer whichhas a T_(g) from about 35° C. to 40° C., for example from about 37° C.to 40° C., wherein the polymer is a poly(a-hydroxyacid) (such as PLA,PGA, PLGA, or PDLLA or a combination thereof), or a blend thereof withPLGA-PEG. Typically, these particles will agglomerate at bodytemperature. The injectable surface treated microparticles may compriseonly poly(α-hydroxyacid) particles or other particle types may beincluded. The microparticles can be formed from a blend ofpoly(D,L-lactide-co-glycolide)(PLGA), PLGA-PEG and PVA which has a T_(g)at or above body temperature. In one embodiment, at body temperature thesurface treated microparticles will interact to form a consolidatedaggregate. The injectable microparticle may comprise onlyPLGA/PLGA-PEG/PVA surface treated microparticles or other particle typesmay be included.

The composition may comprise a mixture of temperature sensitive surfacetreated microparticles and non-temperature sensitive surface treatedmicroparticles. Non-temperature sensitive surface treated microparticlesare particles with a glass transition temperature which is above thetemperature at which the composition is intended to be used. Typically,in a composition comprising a mixture of temperature sensitive surfacetreated microparticles and non-temperature sensitive particles the ratioof temperature sensitive to non-temperature sensitive surface treatedmicroparticles is about 3:1, or lower, for example, 4:3. The temperaturesensitive surface treated microparticles are advantageously capable ofcrosslinking to each other when the temperature of the composition israised to or above the glass transition of these microparticles. Bycontrolling the ratio of temperature sensitive surface treatedmicroparticles to non-temperature sensitive surface treatedmicroparticles it may be possible to manipulate the porosity of theresulting consolidated aggregate. The surface treated microparticles maybe solid, that is with a solid outer surface, or they may be porous. Theparticles may be irregular or substantially spherical in shape.

The surface treated microparticles can have a size in their longestdimension, or their diameter if they are substantially spherical, ofless than about 100 μm and more than about 1 μm. The surface treatedmicroparticles can have a size in their longest dimension, or theirdiameter, of less than about 100 μm. The surface treated microparticlescan have a size in their longest dimension, or their diameter, ofbetween about 1 m and about 40 m, more typically, between about 20 μmand about 40 μm. Polymer particles of the desired size will pass througha sieve or filter with a pore size of about 40 μm.

Formation of the consolidated aggregate from the composition, onceadministered to a human or non-human animal, typically takes from about20 seconds to about 24 hours, for example, between about 1 minute andabout 5 hours, between about 1 minute and about 1 hour, less than about30 minutes, less than about 20 minutes. Typically, the solidificationoccurs in between about 1 minute and about 20 minutes fromadministration.

Typically, the composition comprises from about 20 percent to about 80percent injectable surface treated microparticle material and from about20 percent to about 80 percent carrier; from about 30 percent to about70 percent injectable surface treated microparticle material and fromabout 30 percent to about 70 percent carrier; e.g., the composition maycomprise from about 40 percent to about 60 percent injectable surfacetreated microparticle material and from about 40 percent to about 60percent carrier; the composition may comprise about 50 percentinjectable surface treated microparticle material and about 50 percentcarrier. The aforementioned percentages all refer to percentage byweight.

The surface treated microparticles are loaded, for example, in thesurface treated microparticle or as a coating on the surface treatedmicroparticle, with a pharmaceutically active compound.

The system of the invention can allow for the pharmaceutically activecompound release to be sustained for some time, for example, release canbe sustained for at least about 2 hours, at least about 4 hours, atleast about 6 hours, at least about 10 hours, at least about 12 hours,at least about 24 hours, at least 48 hours, at least a week, more thanone week, at least a month, at least two months, at least three months,at least four months, at least five months, at least six months, atleast seven months, at least eight months, at least nine months, atleast ten months, at least eleven months, at least twelve months, ormore.

In one embodiment, the solid aggregating microparticles that produce apellet in vivo release the therapeutic agent without a burst of morethan about 1 percent to about 5 percent of total payload over a 24 hourperiod.

In one embodiment, the solid aggregating microparticles that produce apellet in vivo release the therapeutic agent without a burst of morethan about 10 percent of total payload over a 24 hour period.

In one embodiment, the solid aggregating microparticles that produce apellet in vivo release the therapeutic agent without a burst of morethan about 15 percent of total payload over a 24 hour period.

In one embodiment, the solid aggregating microparticles that produce apellet in vivo release the therapeutic agent without a burst of morethan about 20 percent of total payload over a 24 hour period.

In one embodiment, the solid aggregating microparticles that produce apellet in vivo release the therapeutic agent without a burst of morethan about 1 percent to about 5 percent of total payload over a 12 hourperiod.

In one embodiment, the solid aggregating microparticles that produce apellet in vivo release the therapeutic agent without a burst of morethan about 5 percent to about 10 percent of total payload over a 12 hourperiod.

In one embodiment, the solid aggregating microparticles that produce apellet in vivo release the therapeutic agent without a burst of morethan about 10 percent of total payload over a 12 hour period.

In one embodiment, the solid aggregating microparticles that produce apellet in vivo release the therapeutic agent without a burst of morethan about 15 percent of total payload over a 12 hour period.

In one embodiment, the solid aggregating microparticles that produce apellet in vivo release the therapeutic agent without a burst of morethan about 20 percent of total payload over a 12 hour period.

In one embodiment, the pharmaceutically active compound is released inan amount effective to have a desired local or systemic physiological orpharmacologically effect.

In one embodiment, delivery of a pharmaceutically active compound meansthat the pharmaceutically active compound is released from theconsolidated aggregate into the environment around the consolidatedaggregate, for example, the vitreal fluid.

In one embodiment, a microparticle comprising a pharmaceutically activecompound of the invention allows a substantially zero or first orderrelease rate of the pharmaceutically active compound from theconsolidated aggregate once the consolidated aggregate has formed. Azero order release rate is a constant release of the pharmaceuticallyactive compound over a defined time; such release is difficult toachieve using known delivery methods.

IX. Manufacture of Microparticles

Microparticle Formation

Microparticles can be formed using any suitable method for the formationof polymer microparticles known in the art. The method employed forparticle formation will depend on a variety of factors, including thecharacteristics of the polymers present in the drug or polymer matrix,as well as the desired particle size and size distribution. The type ofdrug(s) being incorporated in the microparticles may also be a factor assome drugs are unstable in the presence of certain solvents, in certaintemperature ranges, and/or in certain pH ranges.

Particles having an average particle size of between 1 micron and 100microns are useful in the compositions described herein. In typicalembodiments, the particles have an average particle size of between 1micron and 40 microns, more typically between about 10 micron and about40 microns, more typically between about 20 micron and about 40 microns.The particles can have any shape but are generally spherical in shape.

In circumstances where a monodisperse population of particles isdesired, the particles may be formed using a method which produces amonodisperse population of microparticles. Alternatively, methodsproducing polydispersed microparticle distributions can be used, and theparticles can be separated using methods known in the art, such assieving, following particle formation to provide a population ofparticles having the desired average particle size and particle sizedistribution.

Common techniques for preparing microparticles include, but are notlimited to, solvent evaporation, hot melt particle formation, solventremoval, spray drying, phase inversion, coacervation, and lowtemperature casting. Suitable methods of particle formulation arebriefly described below. Pharmaceutically acceptable excipients,including pH modifying agents, disintegrants, preservatives, andantioxidants, can optionally be incorporated into the particles duringparticle formation.

In one embodiment, surface treated microparticles are prepared usingcontinuous chemistry manufacturing processes. In one embodiment, surfacetreated microparticles are prepared using step-wise manufacturingprocesses.

In one embodiment, microparticles containing a therapeutic agent can beprepared as described in PCT/US2015/065894. In one embodiment, themicroparticles are prepared by:

-   -   (i) dissolving or dispersing the therapeutic agent or its salt        in an organic solvent optionally with an alkaline agent;    -   (ii) mixing the solution/dispersion of step (i) with a polymer        solution that has a viscosity of at least about 300 cPs (or        perhaps at least about 350, 400, 500, 600, 700 or 800 or more        cPs);    -   (iii) mixing the therapeutic agent polymer solution/dispersion        of step (ii) with an aqueous non-acidic or alkaline solution        (for example at least approximately a pH of 7, 8, or 9 and        typically not higher than about 10) optionally with a surfactant        or emulsifier, to form a solvent-laden therapeutic agent        encapsulated microparticle,    -   (iv) isolating the microparticles.

In one embodiment, the therapeutic agent is sunitinib.

It has been found that it may be useful to include the alkaline agent inthe organic solvent. However, as described in PCT/US2015/065894, it hasbeen found that adding an acid to the organic solvent can improve drugloading of the microparticle. Examples demonstrate that polyesters suchas PLGA, PEG-PLGA(PLA) and PEG-PLGA/PLGA blend microparticles displaysustained release of the therapeutic agent or its pharmaceuticallyacceptable salt. Polymer microparticles composed of PLGA and PEGcovalently conjugated to PLGA (M_(w) 45 kDa) (PLGA45k-PEG5k) loaded withthe therapeutic agent were prepared using a single emulsion solventevaporation method. The therapeutic agent loading was further increasedby increasing the pH of the aqueous solution. Still further significantincreases in therapeutic agent loading in the microparticles wasachieved by increasing polymer concentration or viscosity. In oneembodiment, the therapeutic agent is sunitinib.

Solvent Evaporation

In this method, the drug (or polymer matrix and drug) is dissolved in avolatile organic solvent, such as methylene chloride, acetone,acetonitrile, 2-butanol, 2-butanone, t-butyl alcohol, benzene,chloroform, cyclohexane, 1,2-dichloroethane, diethyl ether, ethanol,ethyl acetate, heptane, hexane, methanol, methyl tert-butyl ether,pentane, petroleum ether, iso-propanol, n-propanol, tetrahydrofuran, ormixtures thereof. The organic solution containing the drug is thensuspended in an aqueous solution that contains a surface active agentsuch as poly(vinyl alcohol). The resulting emulsion is stirred untilmost of the organic solvent is evaporated, leaving solid microparticles.The resulting microparticles are washed with water and dried overnightin a lyophilizer. Microparticles with different sizes and morphologiescan be obtained by this method.

Microparticles which contain labile polymers, such as certainpolyanhydrides, may degrade during the fabrication process due to thepresence of water. For these polymers, the following two methods, whichare performed in completely anhydrous organic solvents, can be used.

Oil-In-Oil Emulsion Technique

Solvent removal can also be used to prepare particles from drugs thatare hydrolytically unstable. In this method, the drug (or polymer matrixand drug) is dispersed or dissolved in a volatile organic solvent suchas methylene chloride, acetone, acetonitrile, benzene, 2-butanol,2-butanone, t-butyl alcohol, chloroform, cyclohexane,1,2-dichloroethane, diethyl ether, ethanol, ethyl acetate, heptane,hexane, methanol, methyl tert-butyl ether, pentane, petroleum ether,iso-propanol, n-propanol, tetrahydrofuran, or mixtures thereof. Thismixture is then suspended by stirring in an organic oil (such as siliconoil, castor oil, paraffin oil, or mineral oil) to form an emulsion.Solid particles form from the emulsion, which can subsequently beisolated from the supernatant. The external morphology of spheresproduced with this technique is highly dependent on the identity of thedrug.

Oil-In-Water Emulsion Technique

In this method, the drug (or polymer matrix and drug) is dispersed ordissolved in a volatile organic solvent such as methylene chloride,acetone, acetonitrile, benzene, 2-butanol, 2-butanone, t-butyl alcohol,chloroform, cyclohexane, 1,2-dichloroethane, diethyl ether, ethanol,ethyl acetate, heptane, hexane, methanol, methyl tert-butyl ether,pentane, petroleum ether, iso-propanol, n-propanol, tetrahydrofuran, ormixtures thereof. This mixture is then suspended by stirring in anaqueous solution of surface active agent, such as poly(vinyl alcohol),to form an emulsion. Solid particles form from the emulsion, which cansubsequently be isolated from the supernatant. The external morphologyof spheres produced with this technique is highly dependent on theidentity of the drug.

As described in PCT/US2015/065894, microparticles with a therapeuticagent can be prepared using the oil-in-water emulsion method. In oneexample, sunitinib microparticles were prepared by dissolving 100 mgPEG-PLGA (5K, 45) in 1 mL methylene chloride, and dissolving 20 mgsunitinib malate in 0.5 mL DMSO and triethylamine. The solutions werethen mixed together, homogenized at 5000 rpm, 1 minute into an aqueoussolution containing 1% polyvinyl alcohol (PVA) and stirred for 2 hours.The particles were collected, washed with double distilled water, andfreeze dried. In another example, sunitinib microparticles were alsoprepared according to PCT/US2015/065894 by dissolving 200 mg PLGA (2A,Alkermers) in 3 mL methylene chloride, and 40 mg sunitinib malate in 0.5mL DMSO and triethylamine. The solutions were then mixed together andhomogenized at 5000 rpm, 1 minute in 1% PVA and stirred for 2 hours. Theparticles were collected, washed with double distilled water, and freezedried.

Spray Drying

In this method, the drug (or polymer matrix and drug) is dissolved in anorganic solvent such as methylene chloride, acetone, acetonitrile,2-butanol, 2-butanone, t-butyl alcohol, benzene, chloroform,cyclohexane, 1,2-dichloroethane, diethyl ether, ethanol, ethyl acetate,heptane, hexane, methanol, methyl tert-butyl ether, pentane, petroleumether, iso-propanol, n-propanol, tetrahydrofuran, or mixtures thereof.The solution is pumped through a micronizing nozzle driven by a flow ofcompressed gas, and the resulting aerosol is suspended in a heatedcyclone of air, allowing the solvent to evaporate from themicrodroplets, forming particles. Particles ranging between 0.1-10microns can be obtained using this method.

Phase Inversion

Particles can be formed from drugs using a phase inversion method. Inthis method, the drug (or polymer matrix and drug) is dissolved in asolvent, and the solution is poured into a strong non solvent for thedrug to spontaneously produce, under favorable conditions,microparticles or nanoparticles. The method can be used to producenanoparticles in a wide range of sizes, including, for example, about100 nanometers to about 10 microns, typically possessing a narrowparticle size distribution.

Coacervation

Techniques for particle formation using coacervation are known in theart, for example, in GB-B-929 406; GB-B-929 40 1; and U.S. Pat. Nos.3,266,987, 4,794,000, and 4,460,563. Coacervation involves theseparation of a drug (or polymer matrix and drug) solution into twoimmiscible liquid phases. One phase is a dense coacervate phase, whichcontains a high concentration of the drug, while the second phasecontains a low concentration of the drug. Within the dense coacervatephase, the drug forms nanoscale or microscale droplets, which hardeninto particles. Coacervation may be induced by a temperature change,addition of a non-solvent or addition of a micro-salt (simplecoacervation), or by the addition of another polymer thereby forming aninterpolymer complex (complex coacervation).

Low Temperature Casting

Methods for very low temperature casting of controlled releasemicrospheres are described in U.S. Pat. No. 5,019,400 to Gombotz et al.In this method, the drug (or polymer matrix and sunitinib) is dissolvedin a solvent. The mixture is then atomized into a vessel containing aliquid non-solvent at a temperature below the freezing point of the drugsolution which freezes the drug droplets. As the droplets andnon-solvent for the drug are warmed, the solvent in the droplets thawsand is extracted into the non-solvent, hardening the microspheres.

Scale Up

The processes for producing microparticles described in the Examples areamenable to scale up by methods known in the art. Examples of suchmethods include U.S. Pat. Nos. 4,822,534; 5,271,961; 5,945,126;6,270,802; 6,361,798; 8,708,159; and U.S. publication 2010/0143479. U.S.Pat. No. 4,822,534 describes a method of manufacture to provide solidmicrospheres that involves the use of dispersions. These dispersionscould be produced industrially and allowed for scale up. U.S. Pat. No.5,271,961 disclosed the production of protein microspheres whichinvolved the use of low temperatures, usually less than 45° C. U.S. Pat.No. 5,945,126 describes the method of manufacture to producemicroparticles on full production scale while maintaining sizeuniformity observed in laboratory scale. U.S. Pat. Nos. 6,270,802 and6,361,798 describe the large scale method of manufacture of polymericmicroparticles whilst maintaining a sterile field. U.S. Pat. No.8,708,159 describes the processing of microparticles on scale using ahydrocyclone apparatus. U.S. publication 2010/0143479 describes themethod of manufacture of microparticles on large scale specifically forslow release microparticles.

XSpray has disclosed a device and the use of supercritical fluids toproduce particles of a size below 10 μM (U.S. Pat. No. 8,167,279).Additional patents to XSpray include U.S. Pat. Nos. 8,585,942 and8,585,943. Sun Pharmaceuticals has disclosed a process for themanufacture of microspheres or microcapsules, WO 2006/123359, hereinincorporated by reference. As an example, Process A involves five stepsthat include 1) the preparation of a first dispersed phase comprising atherapeutically active ingredient, a biodegradable polymer and anorganic solvent 2) mixing the first dispersed phase with an aqueousphase to form an emulsion 3) spraying the emulsion into a vesselequipped to remove an organic solvent and 4) passing the resultingmicrospheres or microcapsules through a first and second screen therebycollecting a fractionated size of the microspheres or microcapsules and5) drying the microspheres or microcapsules.

Xu, Q. et al. have disclosed the preparation of monodispersedbiodegradable polymer microparticles using a microfluidic flow-focusingdevice (Xu, Q., et al “Preparation of Monodispersed BiodegradablePolymer Microparticles Using a Microfluidic Flow-Focusing Device forControlled Drug Delivery”, Small, Vol 5(13): 1575-1581, 2009).

Duncanson, W. J. et al. have disclosed the use of microfluidic devicesto generate microspheres (Duncanson, W. J. et al. “MicrofluidicSynthesis of Monodisperse Porous Microspheres with Size-tunable Pores”,Soft Matter, Vol 8, 10636-10640, 2012).

U.S. Pat. No. 8,916,196 to Evonik describes an apparatus and method forthe production of emulsion based microparticles that can be used inconnection with the present invention.

X. Process of Preparation of Surface Treated MicroparticlesAbbreviations

DCM, CH₂Cl₂ DichloromethaneDL Drug loadingDMSO Dimethyl sulfoxide

EtOH Ethanol

HA Sodium hyaluronate

hr, h Hour min Minute

NaOH Sodium hydroxideNSTMP Non-surface treated microparticlesPBS Dulbecco's phosphate-buffered saline

PCL Polycaprolactone

PEG Polyethylene glycolPLA Poly(lactic acid)PLGA Poly(lactic-co-glycolic acid)PVA Polyvinyl alcoholRpm Revolutions per minuteRT, r.t. Room temperatureSD Standard deviationSTMP Surface treated microparticles

UV Ultraviolet

Examples 1-30 and FIGS. 1-19 were first presented in U.S. Ser. No.15/349,985 and PCT/US16/61706 and are provided again herein forbackground information for the improved invention described herein.

General Methods

All non-aqueous reactions were performed under an atmosphere of dryargon or nitrogen gas using anhydrous solvents. The structure ofstarting materials, intermediates, and final products was confirmed bystandard analytical techniques, including NMR spectroscopy and massspectrometry.

Materials

Sodium hydroxide (NaOH, catalog #: S318-1, Fisher Chemical), ethanol(EtOH, catalog #: A405-20, Fisher Chemical), Dulbecco'sphosphate-buffered saline (PBS, catalog #: SH3085003, GE HealthcareHyClone™), sodium hyaluronate (HA, catalog #: AC251770010, AcrosOrganics) and Tween 20 (catalog #: BP337-100, Fisher BioReagents) werepurchased from Fisher Scientific. Polyvinyl alcohol (PVA) (88 percenthydrolyzed, MW approximately 25 kD) (catalog #: 02975) was purchasedfrom Polysciences, Inc. Sunitinib malate was purchased from LCLaboratories (catalog #: S-8803). ProVisc® (10 mg/mL, 0.85 mL, catalog#: 21989, Alcon) was purchased from Besse Medical.Poly(lactic-co-glycolic acid) (PLGA) polymer, poly(lactic-acid) (PLA)polymer, and diblock co-polymers of PLGA and polyethylene glycol(PLGA-PEG) were purchased from the Evonik Corporation (RESOMER Select5050 DLG mPEG 5000 (10 wt percent PEG)). A FreeZone 4.5 liter benchtopfreeze dry system was used for lyophilization.

ProVisc® OVD (Ophthalmic Viscosurgical Device) is a sterile,non-pyrogenic, high molecular weight, non-inflammatory highly purifiedfraction of sodium hyaluronate dissolved in physiological sodiumchloride phosphate buffer. It is FDA approved and indicated for use asan ophthalmic surgical aid. Sodium hyaluronate is a derivative ofhyaluronan for clinical use. Hyaluronan, also known as hyaluronic acid,is a naturally occurring glycosaminoglycan found throughout the bodyincluding in the aqueous and vitreous humors of the eye.

Example 1. Preparation of Biodegradable Non-Surface TreatedMicroparticles (NSTMP) Containing PLGA

Polymer microparticles comprising PLGA and diblock copolymer of PLGA andPEG with or without sunitinib malate were prepared using a singleemulsion solvent evaporation method. Briefly, PLGA (560 mg) and PLGA-PEG(5.6 mg) were co-dissolved in dichloromethane (DCM) (4 mL). Sunitinibmalate (90 mg) was dissolved in dimethyl sulfoxide (DMSO) (2 mL). Thepolymer solution and the drug solution were mixed to form a homogeneoussolution (organic phase). For empty NSTMP, DMSO (2 mL) without drug wasused. For drug-loaded NSTMP, the organic phase was added to an aqueous1% PVA solution in PBS (200 mL) and homogenized at 5,000 rpm for 1minute using an L5M-A laboratory mixer (Silverson Machines Inc., EastLongmeadow, Mass.) to obtain an emulsion. For empty NSTMP, 1 percent PVAsolution in water (200 mL) was used.

The emulsion (solvent-laden microparticles) was then hardened bystirring at room temperature for more than 2 hours to allow the DCM toevaporate. The microparticles were collected by sedimentation andcentrifugation, washed three times in water, and filtered through a40-μm sterile Falcon® cell strainer (Corning Inc., Corning, N.Y.). Thenon-surface treated microparticles (NSTMP) were either used directly inthe surface treatment process or dried by lyophilization and stored as adry powder at −20° C. until used.

Example 2. Surface Treatment of Non-Surface Treated Microparticles(NSTMP) Using NaOH(aq)/EtOH

A pre-chilled solution containing 0.25 M NaOH (aq) and ethanol at apredetermined ratio was added to microparticles in a glass vial understirring in an ice bath at approximately 4° C. to form a suspension at100 mg/mL. The suspension was then stirred for a predetermined time(e.g., 3, 6 or 10 minutes) on ice and poured into a pre-chilledfiltration apparatus to remove the NaOH (aq)/EtOH solution. Themicroparticles were further rinsed with pre-chilled water andtransferred to a 50-mL centrifuge tube. The particles were thensuspended in pre-chilled water and kept in a refrigerator for 30 minutesto allow the particles to settle. Following removal of the supernatant,the particles were resuspended and filtered through a 40-μm cellstrainer to remove large aggregates. Subsequently, the particles werewashed twice with water at room temperature and freeze-dried overnight.Detailed formulation information and conditions of NaOH(aq)/EtOH surfacetreatment experiments are listed in Table 1.

TABLE 1 Detailed batch information on NaOH(aq)/EtOH surface treatedmicroparticles Ratio of Batch 0.25M NaOH Treatment Microparticles beforesize (aq) to EtOH Time STMP surface treatment (mg) (v/v) (min) ID S-1(99% PLGA 7525 4A, 200 30/70 3 S-2 1% PLGA-PEG) 200 6 S-3 DL = 18.0% 20010 S-4 S-5 (90% PLGA 7525 4A, 200 50/50 3 S-6 10% PLGA-PEG) 200 6 S-7 DL= 18.9% 200 30/70 6 S-8 S-9 (99% PLGA 7525 4A, 1000 30/70 3 S-10 1%PLGA-PEG) DL = 18.3% S-11 (99% PLGA 7525 2300 30/70 3 S-12 4A, 1%PLGA-PEG) DL = 11.1% S-13 (99% PLGA 7525 3600 30/70 3 S-14 4A, 1%PLGA-PEG) DL = 11.9% S-15 (99% PLGA 7525 2000 30/70 3 S-16 4A, 1%PLGA-PEG) DL = 2.15% S-17 (99% PLGA 7525 2000 30/70 3 S-18 4A, 1%PLGA-PEG) DL = 2.21% DL = Drug loading.

Example 3. In Vitro Assessment of Particle Aggregability

Surface treated microparticles (STMP) were suspended in phosphatebuffered saline (PBS) at a concentration of 200 mg/mL. Thirty or fiftymicroliters of the suspension were injected into 1.5-2.0 mL of PBS orsodium hyaluronate solution (HA, 5 mg/mL in PBS) pre-warmed at 37° C. ina 2 mL microcentrifuge tube using a 0.5 mL insulin syringe with apermanent 27-gauge needle (Terumo or Easy Touch brand). Themicrocentrifuge tube was then incubated in a water bath at 37° C. for 2hours. The aggregability of the microparticles was assessed by visualobservation and/or imaging under gentle agitation by inverting and/ortapping and flicking the tubes containing the microparticles.Non-surface treated microparticles (NSTMP) were used as a control.

A successful surface treatment process is expected to result in STMPthat maintain good suspendability, syringeability and injectability.Most importantly, after the injection into PBS or sodium hyaluronate andthe 2-hour incubation at 37° C., the STMP are expected to formconsolidated aggregate(s) that do not break into smaller aggregates orfree-floating particles under gentle agitation, a key feature thatdifferentiates STMP from NSTMP and STMP with low aggregability.

Example 4. Effect of Temperature During Surface Treatment onMicroparticle Properties

The effect of temperature on surface treatment was studied by comparingparticles treated at room temperature vs. treated at 4° C. The procedurefor surface treatment at room temperature was identical to the proceduredescribed in Example 2 except that it was conducted at room temperatureinstead of at 4° C.

When the surface treatment process was carried out at room temperaturein a mixture of 0.25 M NaOH and EtOH (v/v: 30/70 or 70/30), theparticles aggregated quickly and irreversibly during surface treatment.In contrast, particles treated at 4° C. in a mixture of NaOH/EtOH at thesame volume ratio did not aggregate during the surface treatment processand maintained good suspendability and injectability uponreconstitution. For surface treatment at room temperature in 0.25 M NaOHwithout EtOH, the particles did not aggregate during the 1-hour surfacetreatment. In addition, STMP treated in NaOH failed to aggregatefollowing incubation at 37° C. In contrast, STMP treated around 4° C.did not aggregate during surface treatment, but aggregated followingincubation at 37° C. After lyophilization and reconstitution in aparticle diluent, the STMP were easily loaded into syringes through a27-gauge needle and injected without needle blockage.

Example 5. Effect of PEG Content on the Aggregability of Surface TreatedMicroparticles

TABLE 2 NSTMP and STMP containing different percentages of PLGA:PLGA-PEGPLGA PLGA-PEG Surface Treatment Formulation # (wt %) (wt %) ConditionS-1 99%  1% None S-3 99%  1% 0.25M NaOH/EtOH (30/70, v/v), 6 min S-5 90%10% None S-8 90% 10% 0.25M NaOH/EtOH (30/70, v/v), 6 min

Two batches of NSTMP (S-1 and S-5) and two batches of STMP (S-3 and S-8)containing different weight percentages of PLGA/PLGA-PEG were surfacetreated following the procedure described below and their aggregabilityin both PBS and HA gel were evaluated.

As listed in Table 2 above, formulation S-3 contained 1% PLGA-PEG andS-8 contained 10% of PLGA-PEG. Samples S-3 and S-8 were individuallytreated in a mixture of 0.25M NaOH and EtOH at a volume ratio of 30/70at 4° C. for 6 minutes. Following injection in PBS and incubation at 37°C. for 2 hours, the microcentrifuge tubes were inverted and theaggregability of the particles was assessed by visual inspection. Asillustrated in FIG. 1 , the NSTMP S-1 and S-5 started to disperseimmediately after the tubes were inverted, while the STMP, S-3 and S-8,remained aggregated at the bottom of the tubes without dispersionthroughout the entire period of observation (about 10 minutes).

A similar second experiment was conducted by injecting the same particlesuspensions into HA solutions and incubating the samples at 37° C. for 2hours. Immediately after the tubes were inverted, none of the particlesbecame dispersed, including NSTMP; refer to FIG. 2 . This is likely dueto the higher viscosity of HA that prevents particles from diffusingrapidly in the gel solution. Different from S-1 which remainedaggregated throughout the experiment, S-5 started to become dispersed inHA 2 minutes after the tube was inverted. Without wishing to be bound toany one theory, this may be related to the higher PEG content in S-1that affects the interaction between particles and between the particlesurfaces and HA, and thus the diffusion of S-5 in HA was less hinderedthan that of S-1. Though S-8 remained aggregated after injection andincubation in PBS, it appeared more dispersive in HA solution. Incontrast, S-3, which contains less PEG than S-8, was able to aggregatein both PBS and HA solution. These data indicate that the aggregationand dispersion of STMP can be affected by both the particle compositionand properties of the medium where the STMP are injected.

In a third experiment, samples containing S-1, S-2, S-3, S-4, S-5, S-6,S-7 and S-8 were incubated in PBS at 37° C. for 2 hours. After assessingthe aggregability by inverting the tubes, stronger agitation was appliedby tapping the tubes on the bench, which caused the particle aggregatesto detach from the bottom of the tubes. The integrity of the aggregateswas then examined and compared among different formulations. As shown inFIG. 3 , S-3 (1 percent PLGA-PEG) remained as an integrated singleaggregate after detachment from the bottom of the tube. In comparison,though most particles in S-8 (10% PLGA-PEG) remained as one largeaggregate, many dispersed small aggregates or particles were visible inthe tube. The assay with stronger agitation allowed furtherdifferentiation of the aggregability of different particle formulations.Overall, the data suggest that STMP with lower PEG content generallyform stronger and more consolidated aggregates than STMP with higher PEGcontent.

Example 6. Effect of Surface Treatment with PBS/EtOH on Microparticles

Since NaOH is a strong base that may cause partial degradation ofpolymers and lead to rapid modification of the surface properties ofparticles, a neutral phosphate buffered saline (PBS) solution at pH 7.4was evaluated as an alternative to NaOH and the effect of surfacetreatment using PBS/EtOH on microparticles was studied. The surfacetreatment procedure was identical to that described in Example 2, exceptthat the NaOH solution was replaced with PBS (pH 7.4). The experimentwas performed in an ice bath at approximately 4° C. Detailed formulationcomposition and surface treatment conditions are listed in Table 3. Theaggregability of the surface treated microparticles (STMP) was testedfollowing the procedure described in Example 3.

TABLE 3 Formulation composition and conditions of surface treatment withPBS/EtOH Particle ID Batch PBS/ Treatment before Drug size EtOH TimeSTMP treatment Composition Loading (mg) (v/v) (min) ID S-11 99% PLGA11.1% 200 30/70 3 S-21 S-19 7525 4A, 1% 11.8% 500 S-22 PLGA-PEG 500 S-23500 6 S-24 S-20   0% 200 6 S-25 200 12 S-26

The results of the aggregability test demonstrated that similar tosurface treatment with NaOH/EtOH, all of the STMP treated with PBS/EtOHwere able to form an aggregate after injection into PBS and incubationfor 2 hours at 37° C. The aggregates appeared stable and resistant togentle agitation; refer to FIG. 4 , a photo of 5-21. There was noapparent difference in particle aggregability under in vitro aggregationassay (procedure was conducted as described in Example 3) between theseSTMP and the STMP generated by treatment in NaOH/EtOH. Both drug-loadedSTMP and empty STMP were able to aggregate in PBS, suggesting thesurface treatment process likely has good compatibility with variousparticle formulations with or without drug.

Example 7. Modification of the Surface Treatment Conditions UsingNaOH(Aq)/EtOH

To further optimize the surface treatment conditions with NaOH(aq)/EtOH,the impact of various parameters, such as NaOH concentration,aqueous/EtOH ratio, and treatment time, on surface treatment werestudied (Table 4). It is worth noting that in this Example, the overallmolar concentration of NaOH in the entire aqueous/EtOH mixture was usedas a variable independent of the ratio of aqueous solution to EtOHinstead of using the molarity of NaOH in the aqueous phase only as inExample 2. For example, 0.25M NaOH(aq)/EtOH (v/v: 30/70) in Example 2 isequivalent to 0.075M of NaOH in an aqueous/EtOH (v/v: 30/70) mixture.Thus, the volume ratio of aqueous to EtOH was modified from 30/70 to50/50 and 70/30 with the same total amount of NaOH in the mixture. Inaddition, the amount of NaOH was decreased by 10- or 100-fold withoutchanging the ratio of aqueous solution to EtOH. The different treatmenttime was chosen to achieve comparable effectiveness of surfacetreatment. The procedure for surface treatment on microparticles was thesame as Example 2.

TABLE 4 Detailed batch information on modified NaOH(aq)/EtOH STMP NaOHconcentration Microparticles before Batch in H₂O/EtOH H₂O/EtOH Treatmentsurface treatment size (mg) mixture (M) ratio (v/v) Time (min) STMP IDS-27 (99% PLGA 7525 200 0.075 50/50 10 S-28 4A, 1% PLGA-PEG) 200 50/5020 S-29 DL = 11.3% 200 70/30 15 S-30 200 70/30 30 S-31 200 0.0075 30/703 S-32 200 30/70 10 S-33 200 0.00075 30/70 3 S-34 200 30/70 10 S-35

Example 8. Effect of Surface Treatment Using HCl/EtOH on Microparticles

As surface treatment using an aqueous solution of basic pH (Example 2and Example 7) or neutral pH (Example 6) had been tested previously, theeffect of aqueous solution of acidic pH was evaluated in Example 8. HClwas selected as a representative acid. As shown in Table 5,microparticles were treated for 3 minutes in 0.075 M or 0.0075 M of HClin H₂O/EtOH (v/v: 30/70) mixture, respectively. The procedure forHCl/EtOH surface treatment was the same as in Example 2 except that HCl(aq) was used to replace NaOH (aq).

TABLE 5 Detailed batch information of HCl/EtOH treated STMP HClconcentration Final surface Microparticles before Batch in H₂O/EtOHH₂O/EtOH Treatment treated surface treatment size (mg) mixture (M) ratio(v/v) Time (min) particles S-27 (99% PLGA 7525 200 0.075 30/70 3 S-364A, 1% PLGA-PEG) 200 0.0075 30/70 3 S-37 DL = 11.3%

Example 9. Surface Treatment on Wet Microparticles

In addition to conducting surface treatment on NSTMP by firstre-suspending NSTMP dry powder in an aqueous solution as illustrated inthe previous examples, the feasibility of surface treatment on NSTMPprior to drying (i.e., “wet” microparticles) was also evaluated. It isexpected to be easier to integrate a surface treatment step using “wet”NSTMP into the entire process of scale-up production of STMP than a stepusing dry powder of NSTMP. After obtaining “wet” NSTMP prior tolyophilization as shown in Example 1, an aliquot of the suspension waslyophilized to determine the particle mass per volume. The particlesuspension was then concentrated or diluted accordingly to reach desiredconcentration and cooled down to desired temperature. Other reagentsneeded for surface treatment were then added to the suspension to reachdesired conditions (e.g., concentration of each chemical reagent) asdescribed in Table 6 to start the surface treatment process. The rest ofthe surface treatment process is the same as described on dry particlesin Example 2. The detailed batch information and experimental conditionsare listed in Table 6.

TABLE 6 Detailed batch information and experimental conditions ofsurface treatment on “wet” microparticles Final Micro- surface treatmentsolvent particles Solute Solute H₂O/ Treat- before Batch (base,concentration EtOH ment surface size acid or in H₂O/EtOH ratio Time STMPtreatment (mg) salt) mixture (M) (v/v) (min) ID S-38 (99% 450 NaOH 0.07530/70 3 S-39 PLGA 7525 450 0.0075 30/70 10 S-40 4A, 1% 450 0.075 70/3015 S-41 PLGA-PEG) 450 0.00075 70/30 30 S-42 DL = 11.6% 450 HCl 0.007530/70 3 S-43 450 KCl 0.075 30/70 20 S-44 450 0.35 30/70 20 S-45

Example 10. Optimized Method for Assessing Particle Aggregability InVitro

To improve the method for assessing particle aggregability in vitro, anorbital shaker was used to replace the manual agitation used in Example3.

Fifty microliters of STMP suspension in PBS at 200 mg/mL was injected in2 mL of PBS pre-warmed at 37° C. in a 16-mm round-bottom glass test tubeusing a 1 mL insulin syringe with a permanent 27-gauge needle (Terumo orEasy Touch brand). The test tube was then incubated in a water bath at37° C. for 2 hours. The aggregability of the microparticles was assessedby visual inspection and/or imaging after shaking for 30 seconds at 400rpm on an orbital shaker (Thermo Scientific™ Multi-Platform Shakers:Catalog No. 13-687-700). The test tube containing particles/aggregateswas then turned horizontally for visual assessment of the particleaggregability. NSTMP were used as a control.

As shown in FIG. 17 , all the STMP in Examples 7 and 8 formed anaggregate after the 2-hour incubation and the aggregates remained mostlyintact following 30-second shaking on an orbital shaker. In contrast,NSTMP in S-27 became fully dispersed following the same agitation. S-12described in Example 2 was also included in this assessment to comparethe aggregability of microparticles treated under different conditions.The results suggest all the modified surface treatment conditions inExamples 7 and 8 resulted in STMP with aggregability similar to that ofS-12.

As shown in FIG. 18 , all the STMP (S-39, 5-40, 5-41, 5-42, S-43, S-44,S-45) in Example 9 formed an aggregate after the 2-hour incubation andthe aggregates remained mostly intact following 30-second shaking on anorbital shaker, while NSTMP (S-38) became fully dispersed following thesame agitation. S-42, S-44 and S-45 appeared to aggregate better thanother STMP samples in FIG. 18 and as well as surface treatment on dryparticle in FIG. 17 . The results demonstrate the success andfeasibility of surface treatment on wet microparticles.

Example 11. Determination of Drug Loading

Drug loading was determined by UV-Vis spectrophotometry. Microparticlescontaining sunitinib (10 mg total weight) were dissolved in anhydrousDMSO (1 mL) and further diluted until the concentration of drug was inthe linear range of the standard curve of UV absorbance of the drug. Theconcentration of the drug was determined by comparing the UV absorbanceto a standard curve. Drug loading is defined as the weight ratio of drugto microparticles.

Example 12. In Vitro Drug Release Study

Microparticles containing sunitinib (10 mg total weight) were suspendedin PBS (4 mL) containing 1% Tween 20 in a 6-mL glass vial and incubatedat 37° C. under shaking at 150 rpm. At predetermined time points, 3 mLof the supernatant was withdrawn after particles settled to the bottomof the vial and replaced with 3 mL of fresh release medium. The drugcontent in the supernatant was determined by UV-Vis spectrophotometry orHPLC. Alternatively, the above procedure can be run at 50° C. todetermine an accelerated in vitro drug release rate as shown in FIG. 5 .

Example 13. Studies on the Effects of Surface Treatment onMicroparticles

Besides aggregability, the effect of surface treatment on otherproperties of microparticles was also studied to fully evaluate thefeasibility of surface treatment. As shown in Table 7, in general, theyield and drug loading of STMP (in Example 2) treated for longer periodsof time were slightly lower than those treated for shorter period oftime, suggesting that at 0.25M NaOH/EtOH (v/v: 3:7), the time window forproducing STMP with high yield and loading is narrow (on the order ofminutes). However, under the modified conditions presented in Example 7,the treatment time can be further extended to tens of minutes withoutreducing DL and yield (Table 7) as well as aggregability (Example 10).STMP treated with HCl(aq)/EtOH in Example 8 maintained the DL prior tosurface treatment with relatively high yield (5-36 and 5-37). Inaddition, STMP (5-42, 5-44 and 5-45) produced by surface treatment onwet microparticles in Example 9 also maintained the DL prior to surfacetreatment with comparable yield as STMP produced by surface treatment ondry particles in Example 7 and 8.

TABLE 7 Yield and drug loading of STMP Drug loading (DL) prior Drugloading after Sample Yield to surface treatment surface treatment S-251% 18.0% 14.2% S-3 50% 18.0% 15.3% S-4 36% 18.0% 6.3% S-6 30% 18.9%15.0% S-7 35% 18.9% 14.7% S-8 28% 18.9% 11.6% S-10 67% 18.3% 18.6% S-1268% 11.1% 11.6% S-14 70% 11.9% 12.0% S-16 56% 2.15% 2.11% S-28 43% 11.3%11.8% S-29 49% 11.3% 11.0% S-30 60% 11.3% 10.1% S-31 61% 11.3% 10.6%S-32 44% 11.3% 12.0% S-33 48% 11.3% 11.5% S-34 49% 11.3% 11.5% S-35 58%11.3% 12.0% S-36 61% 11.3% 10.3% S-37 69% 11.3% 11.6% S-42 44% 11.6%11.2% S-44 50% 11.6% 12.0% S-45 43% 11.6% 12.1%

FIG. 6 illustrates representative in vitro drug release profiles ofNSTMP (S-1) and the corresponding STMP (S-2 and S-3) generated from thesame batch of NSTMP. Overall, the release profiles are similar formicroparticles before and after surface treatment except that theinitial release rate of STMP was lower than that of NSTMP. This suggeststhat under the surface treatment conditions drug molecules that arebound to or near the microparticle surface may have been removed duringthe surface treatment process.

Example 14. Wettability of Surface Treated Microparticles

The wettability of representative batches of STMP and NSTMP wascharacterized using the Washburn method. Briefly, two glass capillarytubes with filter bases were separately filled with equivalent masses ofSTMP and NSTMP dry powder. The bottom of the capillary tubes was theninserted into a beaker with water and water was drawn into the tubesover time due to capillary action. The increase in mass of the tube andthe height of water in the tubes were determined as a function of time.The rate of water absorption was relatively rapid in the tube containingNSTMP, but relatively slow for STMP. Similarly, at the end of the test,the mass increase of the tubes was much higher for NSTMP than for STMP,indicating that the surface modification leads to reduction ofwettability of the microparticles likely due to removal of surfactant orboth surfactant and polymer from particle surface.

Example 15. Preparation of Samples S-10, S-12, S-14, S-16, and S-18 andthe Study of their Drug Release Profiles

Samples S-10 to S-16 and S-18 were prepared at a larger scale of 1 to3.6 grams. The yield and drug loading of these batches are shown inTable 6 above. It is worth noting that the drug loading was notsignificantly changed by surface treatment. The average particle size ofthese STMP samples was similar to that of the corresponding NSTMP priorto surface treatment (data not shown). As shown in FIG. 7 , the releaseprofiles of the STMP prepared at a larger scale (S-14 and S-16) weresimilar to the corresponding NSTMP as well, indicating that the surfacetreatment process had minimal effect on the overall drug release.

Example 16. Injectability and Dosing Consistency of Surface TreatedMicroparticles (STMP)

A suspension of STMP (ST-1-5, approximately 10 percent drug loading) atapproximately 200 mg/mL was prepared by suspending the microparticles in5-fold diluted ProVisc® solution containing 2 mg/mL of HA. After anincubation period of 2 hours at room temperature, 10 μL of the STMPsuspension was loaded into a 50 μL Hamilton syringe with an attached27-gauge needle. Following brief vortexing to fully suspend the STMP,the syringe was held horizontally for 2 minutes and vertically for 2minutes prior to injection into a microcentrifuge tube. The injectionwas repeated using 3 different syringes and each syringe was tested 3times. The STMP in each tube was then dissolved in DMSO and the dose ofdrug was determined by UV-Vis spectrophotometry. As shown in Table 8,excellent dosing consistency between injections using the same syringeand between different syringes was observed, suggesting that the STMPsuspension in diluted ProVisc® remained stable at room temperature for asufficient amount of time to allow consistent dosing of the relativelysmall volume of injection (e.g., 10 μL).

TABLE 8 Injectability and dosing consistency of STMP Average doseStandard Standard Standard Standard Sample UV Dose per syringe deviationdeviation Average dose deviation deviation Name Reading (mg) n = 3 (mg)(mg) (%) n = 9 (mg) (mg) (%) Syringe 1.019 .1966 .1974 .0140 7.0942 1-aSyringe .953 .1838 1-b Syringe 1.098 .2118 1-c Syringe 1.136 .2191 .2058.0122 5.9332 .2031 .0129 6.3345 2-a Syringe 1.052 .2029 2-b Syringe1.012 .1952 2-c Syringe 1.052 .2029 .2062 .0156 7.5633 3-a Syringe 1.157.2232 3-b Syringe .998 .1925 3-c

Example 17. Impact of Microparticle Concentration and Particle Diluenton the Aggregation of Surface Treated Microparticles (STMP)

To investigate the effect of particle concentration and diluent on theaggregation of STMP, STMP suspensions (50 μL) in 5-fold diluted ProVisc®at 2 different microparticle concentrations (100 mg/mL and 200 mg/mL)were injected into 4 mL of PBS or HA solution and incubated at 37° C.for 2 hours.

As illustrated in the top panel of FIG. 8C and FIG. 3D), the STMP at 200mg/mL in diluted ProVisc® were able to form a consolidated aggregate inboth PBS and HA following a 2-hour incubation at 37° C. Compared to 200mg/mL STMP suspended in PBS, the aggregation of 200 mg/mL STMP indiluted ProVisc® appeared slower, but the aggregate became moreconsolidated over time, suggesting the HA molecules in the particlediluent may hinder the contact between STMP and slow down theaggregation process. On the other hand, due to its viscoelasticproperties, HA may help keep particles localized and allow sufficienttime for STMP to form an aggregate. The particle aggregates formed in HAalso appeared to have a more spherical morphology than those formed inPBS, suggesting that if a viscoelastic solution is used as the particlediluent, an optimal range of diluent concentration needs to beidentified to improve the overall performance of STMP aggregation.

After the 2-hour incubation, the strength of the aggregates was testedby shaking the test tubes at 250 rpm on an orbital shaker. Asillustrated in the bottom panel of FIG. 8C and FIG. 8D, the aggregateswere able to endure the shear stress generated by shaking with no orlimited dispersion of microparticles.

In comparison, even though the STMP of 100 mg/mL appeared to form anaggregate in PBS (top panel, FIG. 8A), the aggregate appeared less densethan that of the 200 mg/mL STMP in PBS (top panel, FIG. 8C) and tendedto disaggregate into individual microparticles under agitation (bottompanel, FIG. 8A). In addition, the STMP of 100 mg/mL was not able to formone consolidated aggregate in HA at the end of the 2-hour incubationperiod (top panel, FIG. 8B) and many STMP became dispersed in HA uponshaking at 250 rpm (bottom panel, FIG. 8B). Similar to HA molecules inparticle diluent, the HA molecules in the test medium may furtherdecrease particle-particle contact and reduce the chance of forming aconsolidated aggregate. The results suggest that the aggregability ofSTMP decreases at lower microparticle concentration, possibly due toincreased average particle-particle distance and decreased chance ofdirect contact between particles. The aggregation may also be furtherhindered by other molecules, such as HA, in the test medium.

In summary, the aggregation of STMP can be affected by particleconcentration, particle diluent and the environment into which theparticles are delivered. Overall the data demonstrate that underappropriate conditions, the STMP have good aggregability in differentparticle diluents and test media.

Example 18. Aggregation of Surface Treated Microparticles (STMP) in CowEyes Ex Vivo

To evaluate the aggregability of STMP following intravitreal injectionex vivo, enucleated cow eyes (J.W. Treuth & Sons, Catonsville, Md.) wereutilized. The eyes were kept on ice prior to use. Briefly, 30 μL of 200mg/mL STMP, S-10, suspended in 5-fold diluted ProVisc® was injected intothe central vitreous of cow eyes using a 0.5 mL insulin syringe (Terumo)with a 27-gauge needle and three injections were performed in each coweye at different locations. After a 2-hour incubation at 37° C., theeyes were cut open and the aggregates of STMP were examined using adissecting microscope. As shown in FIG. 9 , the injected STMP formedconsolidated aggregates in cow vitreous and no apparent particledispersion was observed.

Example 19. Aggregation of Surface Treated Microparticles (STMP) inRabbit Eyes In Vivo

To study the aggregation of surface treated microparticles in rabbiteyes in vivo, 50 μL of 200 mg/mL STMP S-10 suspended in PBS (FIG. 10A)or 5-fold diluted ProVisc® (FIG. 10B) were injected to the centralvitreous of Dutch Belted rabbit eyes using a 0.5 mL insulin syringe(Terumo) with a 27-gauge needle. Four days after the dosing, the rabbitswere sacrificed and the eyes were nucleated and frozen immediately. Thefrozen eyes were cut into halves and the posterior half of the eye wasthawed at room temperature for 3 minutes to allow isolation of thevitreous from the eye cup, as shown in the left photo of FIG. 10A andFIG. 10B. The frozen vitreous containing particles was placed in acassette to allow the vitreous to thoroughly thaw. The aggregates ofSTMP in the vitreous could be easily separated from vitreous usingforceps, proving the formation of consolidated STMP aggregates in rabbiteyes.

Example 20. Distribution, Tolerability and Pharmacokinetics ofSunitinib-Encapsulated Surface Treated Microparticles (STMP) Followingan Intravitreal (IVT) Injection in Rabbits

The distribution and tolerability of STMP and NSTMP were studied inpigmented New Zealand rabbits (F1) following an intravitreal injectionof the microparticles. ProVisc® was diluted 5-fold in PBS and used as adiluent to prepare particle suspensions of about 200 mg/mL forinjection. Detailed study groups and conditions are presented in Table9.

Complete ocular examinations were performed for up to 7 months after thedosing, using a slit lamp biomicroscope and an indirect ophthalmoscope,to evaluate ocular surface morphology, anterior segment and posteriorsegment inflammation, cataract formation, and retinal changes. A retinallens was used to examine the location, morphology and distribution ofthe microspheres in vitreous. Histological analysis was also performedon enucleated and fixed eyes for up to 7 months. At pre-determined timepoints for up to 7 months, the drug levels of sunitinib (ng/g) invarious ocular tissues (e.g. vitreous, retina, and RPE/choroid) andplasma were also analyzed. FIG. 11A illustrates a representative 1-monthhistology image following injection with surface treated microparticles(STMP) and FIG. 11B illustrates a representative 1-month histologyimages following injection with non-surface treated microparticles(NSTMP).

TABLE 9 Detailed information on rabbit study groups and dosingconditions Microsphere Microsphere Microsphere *SM Drug Injection TypeGroup # Mass Dose Loading Volume With Drug- #1  2 mg 0.2 mg 10% 10 uLsurface loaded #2 10 mg 1.0 mg 10% 50 uL treatment #3 10 mg 0.2 mg  2%50 uL Empty #7 2 and None None 10 uL (Left eye) 10 mg 50 uL (Right eye)Without Drug #4  2 mg 0.2 mg 10% 10 uL surface loaded #5 10 mg 1.0 mg10% 50 uL treatment #6 10 mg 0.2 mg  2% 50 uL Empty #8 2 and None None10 uL (Left eye) 10 mg 50 uL (Right eye) *SM = Sunitinib Malate Dose

Immediately following dosing, the microspheres remained localized at thesite of injection in the vitreous as a depot for all the injections. At1 and 2 months, fundus examination using a retina lens showed that inthe eyes injected with STMP, most particle injections remainedconsolidated in the vitreous without dispersion and no vision impairmentor disturbance was observed. In contrast, particle dispersion was morecommonly observed in the eyes injected with NSTMP.

Histological analysis for up to 7 months showed that overall theinjections were well tolerated with minimal evidence of ocularinflammation or toxicity. No evidence of retinal toxicity (thinning anddegeneration, etc.) was observed with any treatment. With STMP, the onlyeyes with observed inflammation were those with injection-related lenstrauma/cataract and associated secondary lens-induced uveitis, which isbelieved to be associated with the injection procedure and not the STMP;no other evidence of inflammation in eyes dosed with surface treatedmicrospheres was observed (FIG. 11 , left). In some of the eyes dosedwith NSTMP, very mild, but present, inflammation in the vitreous thatmay be associated with the NSTMP was observed (FIG. 11 , right). Theresults suggest that surface treatment not only reduces the chance ofparticle dispersion in the vitreous that can cause visual impairment ordisturbance, but it may also reduce potential intraocular inflammationassociated with microspheres and improve the overall safety of thetreatment.

As shown in FIGS. 14, 15, and 16 , the sunitinib levels in the retina orRPE/choroid of rabbits receiving STMP containing 1 or 0.2 mg ofsunitinib malate were above the K_(i) for sunitinib against VEGFR andPDGFR at 1, 2, and 4 months, respectively. Low levels of sunitinib weredetected in plasma only at 1 and 2 months.

Example 21. Determination of Drug Purity and Impurities in Particles

Sample S-12 (10.5 mg) was measured into an amber vial.N,N-dimethylacetamide (0.3 mL) and acetonitrile (0.6 mL) were added todissolve the particles. Water (2.1 mL) was added and the mixture wasthoroughly mixed. The final concentration of particles in theN,N-dimethylacetamide/acetonitrile/water (v/v 1:2:7) mixture was 3.5mg/mL. The purity of active compound in STMP S-12 was determined by HPLCand is reported in Table 10. The results suggest that the surfacetreatment did not affect the purity of encapsulated drug.

TABLE 10 HPLC analysis of drug purity in STMP Peak Number Retention timeArea (%) 1 0.24 0.157 2 0.78 0.283 3 0.82 0.044 4 1.00 99.39 5 1.120.046 6 1.41 0.084

Example 22. Measurement of Average Size and Size Distribution of SurfaceTreated Microparticles (STMP)

Several milligrams of S-12 were suspended in water. The mean particlesize and distributions were determined using a Coulter Multisizer IV(Beckman Coulter, Inc., Brea, Calif.). The distribution shown in FIG. 12has the following statistics: D10 of 20.98 μm, D50 of 32.32 μm, D90 of41.50 μm, mean of 31.84 μm, and standard deviation of 8.07 μm.

Example 23. Determination of Endotoxin Level in Particle Suspension

Microparticles (5-10 mg, S-12) were added to a sterile vial in abiosafety cabinet. The particles were suspended in endotoxin-free PBS.Using a ToxinSensor™ chromogenic LAL endotoxin assay kit (GenScript USAInc., Piscataway, N.J.) and the instructions provided by themanufacture, the sample's total level of endotoxin was measured. S-12had a low endotoxin level of less than 10 μEU/mg.

Example 24. Toxicity Studies

An acute, non-GLP IVT study was conducted to evaluate the oculartolerability and toxicity of sunitinib malate (free drug) for up to 7days following a single IVT injection. Sunitinib malate was formulatedin phosphate buffered saline and injected bilaterally (0.1 mL) at 0.125or 1.25 mg per eye. At the 1.25 mg/eye dose, histologically significantfindings related to sunitinib included residual test article, lenticularvacuoles/degeneration, mild to minimal inflammatory cell infiltration invitreous, retinal degeneration, detachment, and necrosis. Notoxicologically significant findings were observed at the 0.125 mg/eyedose, which is considered the no-observed-adverse-effect-level (NOAEL)dose.

FIG. 13A, FIG. 13B, and FIG. 13C illustrate select PK profiles forsunitinib malate in the retina, vitreous, and plasma, respectively, frompigmented rabbits.

Example 25. Preparation of Sunitinib Microparticles (not SurfaceTreated)

PLGA (555 mg) and PLGA-PEG5K (5.6 mg) were dissolved in DCM (4 mL).Sunitinib malate (90 mg) was dissolved in DMSO (2 mL). The polymer anddrug solutions were then mixed. The resulting reaction mixture wasfiltered through a 0.22 μm PTFE syringe filter. The resulting reactionmixture was diluted with 1% PVA in PBS (200 mL) in a 250 mL beaker andthen homogenized at 5,000 rpm for 1 minute. (The polymer/drug solutionwas poured into the aqueous phase using homogenization conditions andhomogenized at 5,000 rpm for 1 minute) The reaction was next stirred at800 rpm at room temperature for 3 hours in a biosafety cabinet. Theparticles were allowed to settle in the beaker for 30 minutes andapproximately 150 mL of the supernatant was decanted off. Themicroparticle suspension underwent centrifugation at 56×g for 4.5minutes, the solvent was removed, and the microparticles were thenwashed three times with water. The microparticle size and sizedistribution was determined using a Coulter Multisizer IV prior tolyophilization. The microparticles were lyophilized using a FreeZone4.5-liter benchtop lyophilizer. Light exposure was avoided throughoutthe entire process.

Example 26. General Procedure for the Preparation of Surface TreatedSunitinib Microparticles

Microparticle dry powder was weighed and placed in a small beaker and astirring bar was added. The beaker was placed in an ice bath and cooledto about 4° C. A NaOH/EtOH solution was prepared by mixing NaOH in water(0.25M) with EtOH at 3:7 (v/v) and cooling to about 4° C. The coldNaOH/EtOH solution was added with stirring to the beaker containing themicroparticles to afford a particle suspension of 100 mg/mL. Thesuspension was stirred for 3 minutes at about 4° C. and poured into afiltration apparatus to quickly remove the NaOH/EtOH solution. (Thefiltration apparatus needed to be pre-chilled in a −20° C. freezer priorto use.) Following filtration, the microparticles were rinsed in thefiltration apparatus with ice cold deionized water and transferred to 50mL centrifuge tubes. Each 50 mL centrifuge tube with filled with coldwater to afford a 40 mL particle suspension at a concentration of 5-10mg/mL. The centrifuge tubes were placed in a regenerator and theparticles were allowed to settle for 30 minutes. The supernatant wasthen decanted. The particles were resuspended in cold water and filteredthrough a 40 μm cell strainer to remove any large aggregates. Theparticles were collected by centrifugation (56×g for 4.5 minutes) andwashed twice with water. The product was lyophilized using a FreeZone4.5 liter benchtop lyophilizer. The surface treatment process wasconducted at approximately 4° C. and light exposure was avoidedthroughout the entire process.

Example 27. Method for Determining Accelerating In Vitro Drug Release at50° C.

Microparticles (10 mg) were added to glass scintillation vials. Fourmilliliters of the release medium (1% Tween 20 in 1×PBS at pH 7.4) wasadded into the vials and the mixtures were vortexed. The vials wereshaken on an orbital shaker at 150 rpm in a Fisher general-purposeincubator at 50° C. At pre-determined time points, the appropriate vialwas cooled and the particles were allowed to settle for 10 minutes.Release medium (3 mL) was then carefully removed from the top of thevial and replaced with fresh release medium (3 mL). The vial was thenreturned to the orbital shaker and the amount of drug in the releasemedium was measured by UV spectroscopy. The concentration of drug wasdetermined by comparing to a standard curve for the drug.

Example 28. Preparation of Biodegradable Surface-Treated Microparticles(STMP) Comprising PLA

NSTMP were first produced similarly as described in Example 1. Briefly,PLA and PLGA-PEG were co-dissolved in dichloromethane (DCM) andsunitinib malate was dissolved in dimethyl sulfoxide (DMSO). The polymersolution and the drug solution were mixed to form a homogeneous solution(organic phase). For empty microparticles, DMSO without drug was used.The organic phase was added to an aqueous 1% PVA solution andhomogenized at 5,000 rpm for 1 minute using an L5M-A laboratory mixer(Silverson Machines Inc., East Longmeadow, Mass.) to obtain an emulsion.The emulsion (solvent-laden microparticles) was then hardened bystirring at room temperature for more than 2 hours to allow the DCM toevaporate. The microparticles were collected by sedimentation andcentrifugation, washed three times in water, and filtered through a40-μm sterile Falcon® cell strainer (Corning Inc., Corning, N.Y.). Thenon-surface-treated microparticles (NSTMP) were either used directly inthe surface treatment process or dried by lyophilization and stored as adry powder at −20° C. until used.

A pre-chilled solution containing NaOH and ethanol was added tomicroparticles in a glass vial under stirring in an ice bath atapproximately 4° C. to form a suspension. The suspension was thenstirred for a predetermined time on ice and poured into a pre-chilledfiltration apparatus to remove the NaOH (aq)/EtOH solution. Themicroparticles were further rinsed with pre-chilled water andtransferred to a 50-mL centrifuge tube. The STMP were then suspended inpre-chilled water and kept in a refrigerator for 30 minutes to allow theparticles to settle. Following removal of the supernatant, the particleswere resuspended and filtered through a 40-μm cell strainer to removelarge aggregates. Subsequently, the particles were washed twice withwater at room temperature and freeze-dried overnight.

TABLE 11 Detailed formulation information of STMP comprising PLA NSTMPSurface Treatment STMP Aqueous Particle Treatment ID Polymer Drug PhaseMixing Solution Conc. Time S-46 800 mg PLA 100 100 mg 200 mL of 50000.075M 200 3 min 4A and 8 mg sunitinib 1% PVA in rpm 1 NaOH and mg/mLPLGA-PEG in 4 malate in 1 PBS min 50% EtOH mL DCM mL DMSO S-47 800 mgPLA 100 1 mL DMSO 200 mL of 5000 0.075M 200 3 min 4A and 8 mg 1% PVA inrpm 1 NaOH and mg/mL PLGA-PEG in 4 water min 50% EtOH mL DCM S-48 640 mgPLA 100 2 mL DMSO 200 mL of 5000 0.075M 200 3 min 4A and 6.4 mg 1% PVAin rpm 1 NaOH and mg/mL PLGA-PEG in 4 water min 50% EtOH mL DCM

The in vitro aggregability of the STMP was characterized similarly asdescribed in Example 3. Briefly, STMP were suspended in PBS at 200 mg/mLand 30-50 uL of the suspension was injected into 1.5-2.0 mL of PBSpre-warmed at 37° C. After incubation at 37° C. for 2 hours, theaggregability of the microparticles was assessed by visual observationand/or imaging following gentle mechanical agitation. Overall all STMPdescribed in Table 11 were able to aggregate upon incubation at 37° C.for 2 hours.

Example 29. Distribution, Tolerability and Pharmacokinetics ofSunitinib-Encapsulated STMP Comprising PLA Following an Intravitreal(IVT) Injection in Rabbits

Sunitinib-encapsulated STMP comprising PLA were suspended in ProVisc®diluted 5-fold in PBS to achieve a target dose of 1 mg sunitinib malatein a 50 uL particle suspension. The tolerability and pharmacokineticswere studied in pigmented New Zealand rabbits (F1) following anintravitreal injection of the STMP suspension. At pre-determined timepoints after the dosing, complete ocular examinations were performed andthe drug levels of sunitinib (ng/g) in various ocular tissues (e.g.vitreous, retina, and RPE/choroid) were also analyzed (FIG. 19 ).

Ocular examinations for up to 6 months showed that the STMP were welltolerated in rabbit eyes and remained consolidated in the vitreouswithout dispersion and no vision impairment or disturbance was observed.As shown in FIG. 19 , the sunitinib levels in retina or RPE/choroid ofrabbits receiving STMP containing 1 mg of sunitinib malate were abovethe K_(i) for sunitinib against VEGFR and PDGFR at 10 days and 3 months.

Example 30. Production of Surface-Treated Microparticles (STMP) on aLarger Scale (100 g and Higher)

NSTMP were produced using a continuous flow, oil-in-water emulsificationmethod. The scale of the pilot batches was 100-200 g. A dispersed phase(DP) and a continuous phase (CP) were first prepared. For placebomicroparticles, the DP was prepared by co-dissolving PLGA and PLGA-PEGpolymers in DCM. The CP was a 0.25% PVA solution in water. Fordrug-loaded microparticles, the DP was prepared by dissolving sunitinibmalate in DMSO and mixing with the polymer solution in DCM. The CP was a0.25% PVA solution in PBS (pH approximately 7). Detailed formulationparameters are listed in Table 12. An emulsion was produced by mixingthe DP and the CP using a high shear inline mixer. The solvents in theDP were diluted by the CP, causing the emulsion droplets to solidify andbecome polymer microparticles. The microparticles were then washed withwater using the volume exchange principle with the addition of freshwater and removal of solvent-containing water with a hollow fiberfilter. The washed microparticles were subsequently suspended in asolution containing NaOH and ethanol for surface modification of theNSTMP. This step was performed in a jacketed vessel and the temperatureof the suspension was maintained around 8° C. Several surface treatmentconditions have been tested as shown in Table 12. Following additionalwashing in water and analysis of the microparticle and drugconcentration of in-process samples, the STMP suspension was adjusted totarget concentration prior to filling of glass vials. In some batches,mannitol was added to the final suspension. The vials were thenlyophilized and sealed. The manufacturing process can be completedaseptically and the final product in vials may also be terminallysterilized by E-Beam or gamma irradiation.

TABLE 12 Formulation and process parameters of STMP produced on largerscale NSTMP DP PLGA Sunitinib Mixing Surface Treatment 7525 4A PLGA- DCMMalate DMSO speed Time NaOH (g) PEG5k (g) (g) (g) (g) (rpm) (min) EtOH(mM) Excipient 86 0.86 640 16.5 260 4000 30 30% 0.53 86 0.86 640 16.5260 4000 60 30% 75 86 0.86 640 15.3 260 4000 30 40% 0.075 86 0.86 64015.3 260 4000 30 40% 0.75 86 0.86 640 15.3 260 4000 30 40% 0.75 86 0.86640 15.3 260 4000 30 40% 0.75 86 0.86 640 3600 30 50% 0.75 86 0.86 6403600 30 40% 0.75 86 0.86 640 260 3300 30 50% 0.75 86 0.86 640 15.3 2604000 30 40% 0.75 86 0.86 640 3600 30 60% 0.75 86 0.86 640 15.3 260 400030 40% 0.75 86 0.86 640 3600 30 70% 0.75 86 0.86 640 15.3 260 4000 3050% 0.75 Mannitol 86 0.86 640 15.3 260 4000 30 60% 0.75 Mannitol 86 0.86640 15.3 260 4000 30 70% 0.75 Mannitol 172 1.72 1280 30.6 520 4000 3070% 0.75 Mannitol 172 1.72 1280 3600 30 70% 0.75 172 1.72 1280 3600 2570% 0.75 172 1.72 1280 30.6 520 4000 30 60% 0.75 Mannitol 172 1.72 128030.6 520 4000 30 60% 0.75 Mannitol 172 1.72 1280 3600 25 70% 0.75Mannitol 172 1.72 1280 30.6 520 3800 30 60% 0.75 Mannitol 172 1.72 128030.6 520 4000 30 60% 0.75 172 1.72 1280 30.6 520 4000 30 60% 0.75

The in vitro aggregability of the STMP was characterized by a similarmethod to that in Example 3. Briefly, STMP was suspended in PBS at 200mg/mL and 30-50 uL of the suspension was injected into 1.5-2.0 mL of PBSpre-warmed to 37° C. After incubation at 37° C. for 2 hours, theaggregability of the microparticles was assessed by visual observationand/or imaging following gentle mechanical agitation. In general, allSTMP treated with a solution containing 0.75 mM NaOH and EtOH of 40% orhigher were able to aggregate upon incubation at 37° C. Followingsuspension in hyaluronate solution and injection in PBS, STMP treatedwith a higher concentration of EtOH showed a higher tendency offloatation in PBS, suggesting reduced wettability as a result of thesurface treatment.

Example 31A: Particle Vacuum Treatment Procedure

Particles were machine-filled into 2 mL glass vials and sealed withrubber septum. A vial adapter with a luer-lock opening (source) wasattached to the vial and diluents (e.g., hyaluronic solution (HA)) wereinjected into the vial through the vial adapter. Particles were mixedwith the diluent in the vial by manual tapping or vortex to yield ahomogeneous suspension. A 60 mL VacLok syringe (Merit Medical, SouthJordan, Utah) was attached to the vial adapter and its plunger waspulled to a predetermined volume and locked by turning the plunger perthe manufacturer's instruction (FIG. 20A, FIG. 20C, and FIG. 21 ). Thiscreates a negative pressure in the vial containing particle suspensionas low as approximately 30 Torr depending on the plunger lockingposition. This negative pressure pulls air bubbles away from theparticles and the suspension and thus reduces particle floatation uponinjection later. The vial was then rested in an upright position for apredetermined period (i.e., 10-30 minutes) to allow most of the air tobe removed. After the vacuuming procedure, the 60 mL syringe plunger wasreleased and the syringe was detached from the vial adapter. Thesuspension was remixed by gentle tapping and loaded into syringe forinjection.

Example 31B: Optimized Particle Vacuum Treatment Procedure

The vacuuming step described in Example 31A was optimized. In the methoddescribed in Example 31B, particles were mixed after negative pressurewas created in the vial and the particles were allowed to rest for aperiod of 10-60 minutes. In the method described in Example 31A, anegative pressure was created in the vial prior to mixing and particleswere allowed to rest for 10-30 minutes.

Particles were filled into 2 mL glass vial with rubber septum. A vialadapter with a luer-lock opening was attached to the vial and diluent(e.g., hyaluronic solution (HA)) was injected into the vial through thevial adapter. A 60 mL VacLok syringe (Merit Medical, South Jordan, Utah)was attached to the vial adapter and its plunger was pulled to apredetermined volume and locked by turning the plunger per themanufacturer's instruction (FIG. 20A, FIG. 20C, and FIG. 21 ).

This created a negative pressure in the vials as low as approximately 30Torr depending on the plunger locking position. Particles were mixedwith the diluent in the vial by manual tapping or vortexing under thevacuum created by the VacLok syringe to yield a homogeneous suspension.Due to the vacuum, less air bubbles were generated in the suspensionupon mixing. The vial was then rested in an upright position for apredetermined period (i.e., 10-60 minutes). This further allowed formedair bubbles to be pulled out of the suspension, thus reducing particlefloatation upon injection later. After the vacuuming step, the plungerof the 60 mL syringe was released and the syringe was detached from thevial adapter. The suspension was remixed by gentle tapping and loadedinto a dosing syringe for injection.

With the optimized reconstitution procedure, microparticle floatationduring injection was further reduced as compared to the procedure inExample 31A, especially when the viscosity of the suspension was high(e.g. particle concentration higher than 200 mg/mL). (FIGS. 22A and 22Bare images comparing microparticles that were exposed to the vacuumtreatment of Example 31A (FIG. 22A) and Example 31B (FIG. 22B). As aresult, a more consolidated aggregate/depot was formed by themicroparticles and less particle dispersion was observed as shown inFIG. 22C comparing microparticles exposed to the vacuum treatment ofExample 31A (left) and Example 31B (right).

Example 32. Effect of Vacuum Strength During Vacuum Treatment onParticle Floatation and Aggregation

Particles were suspended in 10× ProVisc (0.125% HA in PBS) to afford afinal concentration of 200 mg/mL. The particle suspensions were vacuumedfor 10 minutes at different strengths of approximately 550 Torr, 143Torr, 87 Torr, and 32 Torr. Following vacuum treatment, the suspensionwas injected into a 37° C. phosphate buffered saline (PBS) in glasstubes and the particle floatation during and after injection wasmonitored. Particles were incubated in the glass tubes at 37° C. for 2hours after injection to assess degree of aggregation. After the 2-hourincubation, the particle aggregate was detached from the bottom of glasstubes by gentle tapping and rotation.

Vacuuming strength inversely correlated with the degree of particlefloatation (FIG. 23A-23L). At 32 Torr, almost no particle floatation wasobserved after injection (FIG. 23H) and the resulting aggregation (FIG.23L) was very good with one large aggregate and minimal free flowingparticles. When no vacuum was pulled, most of the particles floatedafter injection (FIG. 23A) and the aggregation was poor (FIG. 23I). Theintermediate vacuum strengths yielded floatation (FIGS. 23B, 23C, 23F,and 23G) and aggregation (FIGS. 23K and 23L) results in between the twoextreme cases.

Example 33. Impact of Particle Concentration on Vacuuming Outcome

Particle suspensions with concentrations of 200 mg/mL and 400 mg/mL wereprepared by dissolving particles in a 10× ProVisc solution (0.125% HA inPBS) and a 20× ProVisc solution (0.063% HA in PBS), respectively. Theparticles were vacuumed as described in Example 31. Under the sameconditions (vacuum treatment for 20 minutes at approximately 30 Torr),the suspension with 400 mg/mL particles had significantly morefloatation compared to the 200 mg/mL particles (FIG. 24A and FIG. 24B).Without wishing to be bound by any particular one theory, this could bebecause more particles were present in the 400 mg/mL suspension andtrapped more air, rendering a longer time and/or higher vacuumingstrength needed to remove the air. Higher particle concentration alsoincreased the suspension viscosity and slowed down the traveling speedof air out of the suspension.

Example 34. Effect of Vacuum Time on Particle Floatation

Particle suspensions with concentrations of 400 mg/mL were prepared bydissolving particles in a 40× ProVisc solution (0.031% HA in PBS). Theparticles were vacuumed as described in Example 31. Under the samevacuuming strength of approximately 0 Torr and the same particleconcentration of 400 mg/mL, the longer the vacuuming time, the lessfloatation was observed. As shown in FIG. 25A, floatation percentage wasapproximately 20% after 10 minutes of vacuuming treatment compared toapproximately 8% floatation after 30 minutes of vacuuming treatment(FIG. 25B). Without wishing to be bound by any particular one theory,this is because more air was removed after a longer vacuuming time.

Example 35. Effect of High Vacuum Pre-Treatment Compared to Low VacuumPre-Treatment on Particle Floatation

Particle suspensions with concentrations of 400 mg/mL were prepared bydissolving particles in a 20× ProVisc solution (0.063% HA in PBS).Particle vials were sealed under a high vacuum of approximately 35 Torrand the suspensions were vacuumed as described in Example 31. Comparedto particles sealed under a low vacuum of approximately 550 Torr (FIG.26B), the particles subjected to high vacuum treatment (FIG. 26A)exhibited less floatation especially when the suspension wasconcentrated (e.g., 400 mg/mL). FIG. 26A and FIG. 26B show the degree ofparticle floatation after injection from suspensions with 400 mg/mLparticles vacuumed at approximately 35 Torr and 550 Torr for 10 minutes.The suspension prepared in the vial sealed under approximately 35 Torrhad significantly less floatation than the suspension sealed atapproximately 550 Torr. Without being bound to any one theory, this isbecause less air was present in the vial sealed under high vacuum,resulting in less air associated with the particles.

Example 36. Effects of Excipient Type Concentration on Floatation

Particles were suspended in solutions of 1% or 10% sucrose, mannitol, ortrehalose to afford solutions with concentrations of approximately 60mg/mL. The particles were then sonicated for a few minutes, flash frozenin −80° C. ethanol and lyophilized overnight. The lyophilized particleswere then suspended in water and injected into 37° C. PBS or hyaluronicacid (HA) solution (5 mg/mL) to assess floatation and aggregation.Control particles had no excipients added.

Upon injection into PBS and HA solution, particles with excipients(FIGS. 27A-27J) had less floatation compared to controls (FIGS. 27K and27L). Particle sonicated in 10% sucrose excipient (FIGS. 27B and 27D)yielded less floatation than 1% sucrose (FIGS. 27A and 27C), while 1%and 10% mannitol (FIGS. 27E-27H) or trehalose (FIGS. 27I and 27J)yielded similar degree of floatation.

Particles were incubated in the glass tubes at 37° C. for 2 hours afterinjection to assess degree of aggregation. After the 2-hour incubation,the particle aggregate was detached from the bottom of glass tubes bygentle tapping and rotation. Particles with excipients exhibitedaggregation whereas particles without excipients had poor aggregation(FIG. 28 ).

Example 37. The Effect of Sonication on Particle Floatation andAggregation

Particles were suspended in HA solution, sonicated for a few minutes,and injected into 37° C. PBS. The sonicated particles had lessfloatation and better aggregation compared to the control (FIGS. 29A and29B). Without wishing to be bound to any one theory, this is becausesonication introduces high frequency agitation and can remove the airassociated with the particles, reduce floatation, and improveaggregation as shown in FIG. 30 .

Example 38: Longer-Lasting Sunitinib-Encapsulated Polymer MicroparticlesPreparation of Sunitinib Particles

Polymer microparticles comprising PLA, PLGA and/or diblock copolymer ofPLGA and PEG encapsulating sunitinib malate were prepared using a singleemulsion solvent evaporation method. PLA, PLGA and PLGA-PEG werepurchased from Evonik Corporation (Birmingham, Ala.). Sunitinib malate(SM) was purchased from Teva Pharmaceutical Industries Ltd. (Parsippany,N.J.) or LC Laboratory (Woburn, Mass.).

Briefly, PLA, PLGA and PLGA-PEG of selected ratios were weighed andco-dissolved in dichloromethane (DCM) at pre-determined concentration.Sunitinib malate was dissolved in an organic solvent such as dimethylsulfoxide (DMSO) at pre-determined concentration. After mixing thepolymer solution and the drug solution to form a homogeneous solution(organic phase), the organic phase was homogenized in an aqueoussolution of polyvinyl alcohol (PVA) (Mw 25 kD, 88% hydrolyzed) in aphosphate buffer saline (PBS) solution with a pH ˜7.4 using an L5M-Alaboratory mixer or a Verso laboratory in-line mixer (Silverson MachinesInc., East Longmeadow, Mass.) to form particles. Detailed formulationand process parameters are presented in Table 13.

Particles were hardened by stirring at room temperature for >2 hr toallow DCM to evaporate, and then collected by centrifugation and washedprior to drying by lyophilization. Mean particle sizes and particle sizedistributions were determined using a Coulter Multisizer IV (BeckmanCoulter, Inc., Brea, Calif.). Lyophilized particles were stored at −20°C. until use.

Determination of Drug Loading and Encapsulation Efficiency

Drug loading was determined by UV absorbance. 10 mg of particlescontaining sunitinib malate were dissolved in 1 mL of anhydrous DMSO.Appropriate dilutions of this solution were made in DMSO until theconcentration of drug was in the linear range of the standard curve ofUV absorbance for the drug. The concentration of the drug was determinedby comparison to the standard curve.

In Vitro Drug Release at Body Temperature

5 mg of dried particles were suspended in 1 mL of PBS (pH 7.4) andincubated at 37° C. on a rotating platform (140 rpm). At selected timepoints, supernatant was collected by centrifugation and particles wereresuspended in 1 mL of fresh PBS. The UV absorbance of the collectedrelease medium was measured and the concentration of drug at each timepoint was determined by comparison to a standard curve for the drug.

Influence of Polymer Composition on the Release Kinetics of Sunitinib

Particles composed of a polymer blend including PLA, PLGA, andPLGA5050-PEG5k (10% PEG) were made as described above. Polymers withdifferent hydrophobicity (LA/GA ratio) and MW were tested. The drugloading and encapsulation efficiency were characterized. The polymercomposition, formulation parameters, and in vitro characterization dataof select formulations are shown in Table 13, Table 14, Table 15, Table16, and Table 17.

TABLE 13 Polymer Composition, Formulation Parameters, and In VitroCharacterization of Sunitinib-encapsulated Microparticles. Ratio andPolymer Sunitinib conc. of conc. in Malate in DCM to Drug Mean InPolymer polymer DCM DMSO DMSO loading Size Vitro ID Compositioncomposition (mg/mL) (mg/mL) ratio (wt %) (μm) burst % SM PLGA 75:25^(a)100/1 140 45 2:1 12.0 31 0.92 72 4A/ (99% PLGA PLGA-PEG and 1% PLGA-PEG)SM PLA 100/1 200 100 4:1 13.3 26 0.41 60 4A/ (99% PLA PLGA-PEG and 1%PLGA-PEG) SM PLA 100/1 200 100 2:1 18.5 40 2.08 61 4A/ (99% PLA PLGA-PEGand 1% PLGA-PEG) SM PLA 4A/ 90/10/1 200 100 2:1 18.6 40 1.81 62 PLGA/(99% PLA, PLGA-PEG PLGA blend and 1% PLGA-PEG) SM PLA 4A/ 70/30/1 200100 2:1 18.5 38 2.23 63 PLGA/ (99% PLA, PLGA-PEG PLGA blend and 1%PLGA-PEG) SM PLA 4A/ 50/50/1 200 100 2:1 17.6 38 1.92 64 PLGA/ (49.5%PLGA-PEG PLA, 49.5% PLGA and 1% PLGA-PEG) ^(a)PLGA 75:25 is a PLGApolymer where the ratio of lactide units to glycolide units is 75 to 25

TABLE 14 Polymer Composition, Formulation Parameters, and In VitroCharacterization of Sunitinib-encapsulated Microparticles. Ratio andPolymer Sunitinib conc. of conc. in Malate in DCM to Drug Mean InPolymer polymer DCM DMSO DMSO loading Size Vitro ID Compositioncomposition (mg/mL) (mg/mL) ratio (wt %) (μm) burst % SM PLA 95/5/1 200100 2:1 18.2 26 2.16 65 4A/PLGA (99% PLA, 5050^(a) PLGA blend 4A/ and 1%PLGA-PEG = PLGA-PEG) 95/5/1 SM PLA 90/10/1 200 100 2:1 20.3 22 2.49 664A/PLGA (99% PLA, 5050^(a) PLGA blend 4A/ and 1% PLGA-PEG = PLGA-PEG)90/10/1 SM PLA 95/5/1 200 100 2:1 17.4 25 1.75 67 4A/PLGA (99% PLA,5050^(a) PLGA blend 5A/ and 1% PLGA-PEG = PLGA-PEG) 95/5/1 SM PLA70/30/1 200 100 2:1 18.1 25 2.03 68 4A/PLGA (99% PLA, 5050^(a) PLGAblend 5E/ and 1% PLGA-PEG = PLGA-PEG) 70/30/1 SM PLA 90/10/1 200 100 2:116.5 27 1.07 69 4A/PLGA (99% PLA, 5050^(a) PLGA blend 5E/ and 1%PLGA-PEG = PLGA-PEG) 90/10/1 SM PLA 70/30/1 200 100 2:1 15.2 24 6.61 704A/PLGA (99% PLA, 7525^(b) PLGA blend 3A/ and 1% PLGA-PEG = PLGA-PEG)70/30/1 SM PLA 90/10/1 200 100 2:1 18.1 25 3.78 71 4A/PLGA (99% PLA,7525^(b) PLGA blend 3A/ and 1% PLGA-PEG = PLGA-PEG) 90/10/1 ^(a)PLGA50:50 is a PLGA polymer where the ratio of lactide units to glycolideunits is 50 to 50 ^(b)PLGA 75:25 is a PLGA polymer where the ratio oflactide units to glycolide units is 75 to 25

TABLE 15 Polymer Composition, Formulation Parameters, and In VitroCharacterization of Sunitinib-encapsulated Microparticles. Ratio andPolymer Sunitinib conc. of conc. in Malate in DCM to Drug Mean InPolymer polymer DCM DMSO DMSO loading Size Vitro ID Compositioncomposition (mg/mL) (mg/mL) ratio (wt %) (μm) burst % SM PLA 4A/ 90/10/1200 110 2:1 19.0 26 0.87 74 PLGA 75:25^(a) (99% PLA, 4A/ PLGA blendPLGA-PEG and 1% PLGA-PEG) SM PLA 4A/ 70/30/1 200 110 2:1 18.8 25 1.78 75PLGA 75:25^(a) (99% PLA, 4A/ PLGA blend PLGA-PEG and 1% PLGA-PEG) SM PLA4A/ 50/50/1 200 110 2:1 18.1 28 3.03 76 PLGA 75:25^(a) (49.5% 4A/ PLA,49.5% PLGA-PEG PLGA and 1% PLGA-PEG) SM PLA 4A/ 100/1 200 110 2:1 18.828 1.52 77 PLGA-PEG (99% PLA and 1% PLGA-PEG) ^(a)PLGA 75:25 is a PLGApolymer where the ratio of lactide units to glycolide units is 75 to 25

TABLE 16 Polymer Composition, Formulation Parameters, and In VitroCharacterization of Sunitinib-encapsulated Microparticles. Ratio andPolymer Sunitinib conc. of conc. in Malate in DCM to Drug Mean InPolymer polymer DCM DMSO DMSO loading Size Vitro ID Compositioncomposition (mg/mL) (mg/mL) ratio (wt %) (μm) burst % SM PLGA 75:25^(a)100/1 140 45 2:1 13.3 28 n/a 78 4A/ (99% PLGA PLGA-PEG and 1% PLGA-PEG)SM PLA 100/1 200 100 4:1 12.0 24 n/a 79 4A/ (99% PLA PLGA-PEG and 1%PLGA-PEG) ^(a)PLGA 75:25 is a PLGA polymer where the ratio of lactideunits to glycolide units is 75 to 25

The in vitro release kinetics of the formulations in Table 13 arepresented in FIG. 31 . SM62 and SM63 exhibit release kinetics that arerelatively linear over 180 days. The in vitro release kinetics of theformulations in Table 14 are presented in FIG. 32 . SM65 exhibitsrelease kinetics that are relatively linear by 100 days with a slightincrease in release rate beyond 120 days. SM 66 exhibits relativelylinear release by 100 days and faster release in the first 40 days.There is also a slight increase in release rate beyond 120 days. SM71exhibits relative higher burst and relatively linear release by 100 dayswith a slight increase in release rate past 100 days. A previouslydeveloped formulation (SM72) that does not contain PLA was included forcomparison. The in vitro release kinetics of the formulations in Table15 are presented in FIG. 33 . The in vitro release kinetics of theformulations of SM60, SM72, and a 7:3 mass ratio blend of SM79/SM78described in Table 16 are presented in FIG. 34 . As shown in FIG. 31 ,all formulations containing PLA have substantially longer duration ofrelease than SM72 which does not contain PLA. As shown in FIG. 31 , FIG.32 , and FIG. 33 , by changing the composition of the polymer blendincluding the choice of PLGA and/or varying the ratio between polymers,the release kinetics can be fine-tuned to improve the linearity of drugrelease. Alternatively, a more linear release profile may also beobtained by blending different particle formulations that have differentrelease kinetics, as demonstrated in FIG. 34 .

To further improve the drug loading and extend the release duration ofmicroparticle formulations shown in Tables 13-16, formulations describedin Table 17 were made using different polymers with longer MW. The digitin the name of polymer, such as 4A, 6E, or 8E, indicates the viscosityrank of these polymers. Therefore, the larger the number, the higher theviscosity and larger the molecular weight.

Polymer utilized in the formulations described in Table 17 haveviscosity ranks of 6E and 8E, while the polymer formulations describedin Tables 13-16 have viscosity ranks of 3A, 4A, 5A, and 5E. FormulationsSM81, SM82, SM83, and SM84 contain PLGA 75:25 8E, which has anapproximate Mw (weight-average molecular weight) of 141 KDa and an Mn(number-average molecular weight) of 84 KDa. As shown in Table 17, drugloading of these formulations was significantly improved fromapproximately 20% as shown in Tables 13-16 to approximately 30-40% asshown in Table 17.

TABLE 17 Polymer Composition, Formulation Parameters, and In VitroCharacterization of Sunitinib-encapsulated Microparticles. PolymerSunitinib DCM conc. Malate to Drug Mean Polymer in DCM in DMSO DMSOloading Size ID Composition (mg/mL) (mg/mL) ratio (wt %) (μm) SM PLA 6E/100 105 2:1 27.0 28.1 80 PLGA-PEG = 100/1 (99% PLA and 1% PLGA-PEG) SMPLGA 7525 80 105 2:1 30.1 24.5 81 8E/PLGA-PEG = 100/1 (99% PLGA and 1%PLGA-PEG) SM PLGA 7525 100 105 2:1 27.9 32.7 82 8E/PLGA-PEG = 100/1 (99%PLGA and 1% PLGA-PEG) SM PLGA 7525 50 75 2:1 31.0 22.9 83 8E/PLGA-PEG =100/1 (99% PLGA and 1% PLGA-PEG) SM PLGA 7525 50 105 2:1 37.2 25.0 848E/PLGA-PEG = 100/1(99% PLGA and 1% PLGA-PEG)

Four additional lots of sterile longer-lasting formulations aredescribed in Tables 18A. The mean, median, standard deviation, d10, d50,and d90 of the microparticles are give in Table 181. All microparticleswere formulated with different ratios of PLA 4A/PLGA 7525 4A/PLGA-PEG.All four lots exhibited good aggregation in vitro and exhibited releaserates of approximately 20%. The in vitro release data following dosingin rabbits of the four lots characterized in Table 18A and 18B is shownin FIG. 35 . The release rate of microparticles formulated without PLA(SM 72) is shown for comparison. The formulations shown in Tables 18Aand 18B were produced by an in-line mixer, sterilized, andsurface-treated.

TABLE 18A Characterization of PLA/PLGA/PLGA-PLA Blended MicroparticlesComposition In (PLA vitro 4A/PLGA In vitro burst 7525 In vitroaggregation at Mean 4A/ DL Endotoxin aggregation (10 × 37° C. YieldYield size ID PLGA-PEG) (%) (surface) (PBS/PBS) PV/PBS) (~3 h) (g) (%)(um) SM 90/10/1 19.02 0.000055 Good Good 0.87 4.55 34.7 25.17 90 (99%PLA, PLGA blend and 1% PLGA-PEG) SM 70/30/1 18.78 0.000034 Good Good1.88 6.01 46.6 25.33 91 (99% PLA, PLGA blend and 1% PLGA-PEG) SM 50/50/118.09 0.00022 Good Good 3.28 3.58 27.6 27.84 92 (99% PLA, PLGA blend and1% PLGA-PEG) SM 100/0/1 18.76 0.00023 Good Good 1.59 4.24 32.9 28.15 93(99% PLA and 1% PLGA-PEG)

TABLE 18B Characterization of PLA/PLGA/PLGA-PLA Blended MicroparticlesComposition (PLA 4A/PLGA 7525 Mean Median S.D. ID 4A/PLGA-PEG) (μm) (μm)(μm) d10 (μm) d50 (μm) d90 (μm) SM90 90/10/1 (99% PLA, 25.17 25.69 6.68516.33 25.69 32.84 PLGA blend and 1% PLGA-PEG) SM91 70/30/1 (99% PLA,25.33 25.87 7.866 14.48 25.87 34.92 PLGA blend and 1% PLGA-PEG) SM9250/50/1 (99% PLA, 27.84 27.82 8.6 16.81 27.82 38.98 PLGA blend and 1%PLGA-PEG) SM93 100/0/1 (99% PLA 28.15 28.15 8.704 16.8 28.15 39.37 and1% PLGA-PEG)

A comparison of the in vitro release of three lots of PLA 4A particlesis shown in FIG. 36 . Two of the microparticle lots (SM 94 and SM 61)were homogenized via a small probe, while one lot (SM 93) washomogenized via an in-line mixer. SM 94 and SM 61 were notsurface-treated, while SM 93 was surface-treated. Furthercharacterization details for the three lots are shown in Tables 19A and19B.

TABLE 19A Characterization of Microparticles formulated with PLA PolymerHomo- Surface conc. API conc. DCM to genizer treated in DCM in DMSO DMSOID Composition type (YIN) (mg/mL) (mg/mL) ratio SM 99% PLA Small N 200100 4:1 94 4A/1% probe PLGA-PEG SM 100% PLA Small N 200 100 2:1 61 4A/1%probe PLGA-PEG SM 100% PLA In-line Y 200 110 93 4A/1% mixer PLGA-PEG

TABLE 19B Drug loading, mean size, and in vitro burst percent ofmicroparticles formulated with PLA Drug loading Mean Size ID Composition(wt %) (μm) In vitro burst % SM94 99% PLA 13.3 26 0.41 4A/1% PLGA- PEGSM61 100% PLA 18.5 40 2.08 4A/1% PLGA- PEG SM93 100% PLA 18.8 28 1.594A/1% PLGA- PEG

Example 39. In Vitro Release of Particle Blending

The in vitro release of particle blending is shown in FIG. 37 . Therelease rate of blends of different formulations of microspheres (9:1PLA:PLGA, 7:3 PLA:PLGA, and 5:5 PLA:PLGA) are shown and compared toformulations SM 94 and SM 72. The calculated release rate and the actualrelease rate is shown for each of the blends.

Example 40. In Vivo Injection of Sunitinib Encapsulated Microparticles

Ocular Drug Levels after an Intravitreal Injection

Drug-containing microparticles (1 mg sunitinib) were injected (0.05 mL)into the vitreous of pigmented New Zealand rabbits using a 27G needleand the ocular levels of sunitinib were assessed for 9 months. Completeocular examinations were performed 10 days after dosing and monthlythereafter for 9 months, using a slit lamp biomicroscope and an indirectopthalmoscope, to evaluate ocular surface morphology, anterior segmentand posterior segment inflammation, cataract formation, and retinalchanges. A retinal lens was used to examine the location, morphology anddistribution of the microspheres in vitreous. At time points of 3, 6,and 9 months, the drug levels of sunitinib (ng/g) in various oculartissues (e.g. vitreous, retina, and RPE/choroid) and plasma were alsoanalyzed.

After injection, microparticles were shown to coalesce in the inferiorvitreous into an immobile, implant-like depot that remains outside ofthe visual axis. Slit-lamp and fundus examinations showed no OE findingsin any of the eyes dosed with the formulations or with the placeboformulation for the entire in-life portion (9-months post dose).

Both SM60 and a blend of SM60 and SM72 at a 7:3 mass ratio wereevaluated. The in vivo release profiles of the formulations are shown inFIG. 38 . The data show that the duration of release of both SM60 andthe blend of SM60 and SM72 was significantly longer than that of SM72.The release profile of the blend of SM60 and SM72 is also more linearthan that of SM60. In addition, as shown in FIGS. 39A and 39B,relatively high drug levels were maintained in the rabbit eyes injectedwith SM60 or the blend of SM60 and SM72 for at least 9 months.

As shown in FIGS. 38, 39A, and 39B (in vitro and in vivo drug releasekinetics), the inclusion of PLA in the formulation extends the durationof drug release by up to 6 months with a good correlation seen betweenin vitro and in vivo release kinetics. In addition, the PLA-basedformulations maintain pharmacologically active levels in retina/RPEchoroid for at least 9-months post-dose.

Pharmacokinetics (PK) and Toxicity Study for Longer-LastingSunitinib-Encapsulated Polymer Microparticles

Drug-containing microparticles (˜0.75 mg sunitinib) (SM74, 75 and 76)were injected (0.02 mL) into the vitreous of pigmented Dutch Beltedrabbits using a 27G needle and the ocular levels of sunitinib wereassessed for up to 8 months. To evaluate ocular surface morphology,anterior segment and posterior segment inflammation, cataract formation,and retinal changes, ocular examinations were performed 10 days and 1,2, 4, 6 and 8 months post-injection using a slit lamp biomicroscope andfundus examination A retinal lens was used to examine the location,morphology and distribution of the microspheres in vitreous. At timepoints of 10 days and 1, 2, 4, 6 and 8 months the drug levels ofsunitinib (ng/g) in various ocular tissues (e.g. retina and RPE/choroid)were also analyzed. FIG. 40A illustrates the remaining drug in thecentral retina and RPE/choroid area and FIG. 40B illustrates theremaining drug in the eye. The in vivo data indicate that theseformulations can safely and effectively last at least 8 months in rabbiteyes.

After injection, microparticles were shown to coalesce in the inferiorvitreous into an immobile, implant-like depot that remains outside ofthe visual axis. Slit-lamp and fundus examinations showed no OE findingsin any of the eyes dosed with the formulations or with the placeboformulation for the partial in-life portion (8-months post dose).

As shown in FIG. 40A and FIG. 40B, increasing the PLA ratio in theformulation extends the duration of drug release in vivo. SM76 with aratio of PLA:PLGA:PLGA-PEG of 50:50:1 exhibited drug release of 6months, while SM75 (ratio of 70:30:1) exhibited a drug release of 8months. SM74, which was formulated with a PLA:PLGA:PLGA-PEG ratio of90:10:1 exhibited a drug release rate of greater than >8 months.

This specification has been described with reference to embodiments ofthe invention. However, one of ordinary skill in the art appreciatesthat various modifications and changes can be made without departingfrom the scope of the invention as set forth herein. Accordingly, thespecification is to be regarded in an illustrative rather than arestrictive sense, and all such modifications are intended to beincluded within the scope of invention.

We claim:
 1. A method for the treatment of an ocular disorder selectedfrom glaucoma, wet-age related macular degeneration, dry-age relatedmacular degeneration, or a disorder related to an increase inintraocular pressure comprising suprachoroidal administration of aneffective amount of solid aggregating biodegradable microparticlesoptionally in a pharmaceutically acceptable carrier wherein the solidaggregating biodegradable microparticles comprise a prodrug of atherapeutically active compound encapsulated in (a)poly(lactic-co-glycolic acid) (PLGA) and/or polylactic acid (PLA) and(b) poly(lactic-co-glycolic acid) conjugated to polyethylene glycol(PLGA-PEG), and a surfactant, wherein the microparticles: (i) have amean diameter between 10 μm and 60 μm; (ii) have been surface-modifiedwith a surface treatment agent to partially degrade surface polymer at atemperature less than about 18° C. wherein the surface treatment agentcomprises an aqueous base and an organic solvent; (iii) aggregate invivo to form at least one larger pellet in vivo that provides sustaineddrug delivery in vivo for at least three months; and (iv) wherein theprodrug is selected from the formula:

or a pharmaceutically acceptable salt thereof wherein x and y areindependently selected from 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10; and x′and y′ are independently selected from 1, 2, 3, 4, 5, 6, 7, 8, 9, and10.
 2. The method of claim 1, wherein x and y are independently selectedfrom 1, 2, 3, 4, 5, and
 6. 3. The method of claim 1, wherein x′ and y′are independently selected from 1, 2, 3, 4, 5, and
 6. 4. The method ofclaim 1, wherein y is 2, 3, or 4 and y′ is 2, 3, or
 4. 5. The method ofclaim 1, wherein the prodrug is of the formula

or a pharmaceutically acceptable salt thereof.
 6. The method of claim 5,wherein y is 2, 3, or 4 and y′ is 2, 3, or
 4. 7. The method of claim 6,wherein the prodrug is of the formula

or a pharmaceutically acceptable salt thereof.
 8. The method of claim 6,wherein the prodrug is of the formula

or a pharmaceutically acceptable salt thereof.
 9. The method of claim 1,wherein at least one pellet provides sustained drug delivery for atleast 4 months.
 10. The method of claim 1, wherein at least one pelletprovides sustained drug delivery for at least 5 months.
 11. The methodof claim 1, wherein at least one pellet provides sustained drug deliveryfor at least 6 months.
 12. The method of claim 1, wherein the solidaggregating biodegradable microparticles have a mean diameter betweenabout 20 and 50 μm.
 13. The method of claim 1, wherein the solidaggregating biodegradable microparticles have a mean diameter betweenabout 20 and 40 μm.
 14. The method of claim 1, wherein the solidaggregating biodegradable microparticles have a mean diameter betweenabout 20 and 30 μm.
 15. The method of claim 1, wherein the solidaggregating biodegradable microparticles have a mean diameter betweenabout 25 and 40 μm.
 16. The method of claim 1, wherein the solidaggregating biodegradable microparticles have a mean diameter betweenabout 25 and 35 μm.
 17. The method of claim 1, wherein the aqueous baseis a hydroxide base.
 18. The method of claim 1, wherein the aqueous baseis sodium hydroxide.
 19. The method of claim 1, wherein the aqueous baseis potassium hydroxide.
 20. The method of claim 17, wherein the organicsolvent is an alcohol.
 21. The method of claim 20, wherein the alcoholis ethanol.
 22. The method of claim 20, wherein the alcohol is methanol.23. The method of claim 21, wherein the surface treatment agentcomprises ethanol and sodium hydroxide.
 24. The method of claim 1,wherein the surface has been modified at a temperature not more than 16°C.
 25. The method of claim 1, wherein the surface has been modified at atemperature not more than 10° C.
 26. The method of claim 1, wherein thesurface has been modified at a temperature not more than 8° C.
 27. Themethod of claim 1, wherein the surface has been modified at atemperature not more than 5° C.
 28. The method of claim 1 for thetreatment of glaucoma.
 29. The method of claim 1 for the treatment ofwet-age related macular degeneration.
 30. The method of claim 1 for thetreatment of dry-age related macular degeneration.
 31. The method ofclaim 1 for the treatment of a disorder related to an increase inintraocular pressure.
 32. The method of claim 1 wherein the oculardisorder for treatment is in a human.